diff --git a/docs/Entities.md b/docs/Entities.md
new file mode 100644
index 0000000000..67e3856e7b
--- /dev/null
+++ b/docs/Entities.md
@@ -0,0 +1,153 @@
+## Entities
+
+Entities are one of the core concepts of DDD (Domain Driven Design). Eric Evans describe it as "*An object that is not fundamentally defined by its attributes, but rather by a thread of continuity and identity*".
+
+An entity is generally mapped to a table in a relational database.
+
+### Entity Class
+
+Entities are derived from `Entity<TKey>` class as shown below:
+
+```C#
+public class Person : Entity<int>
+{
+    public string Name { get; set; }
+
+    public DateTime CreationTime { get; set; }
+
+    public Person()
+    {
+        CreationTime = DateTime.Now;
+    }
+}
+```
+
+> If you do not want derive your entity from the base `Entity<TKey>` class, you can directly implement `IEntity<TKey>` interface.
+
+`Entity<TKey>` class just defines an `Id` property with the given primary **key type**, which is `int` in the sample above. It can be other types like `string`, `Guid`, `long` or whatever you need.
+
+Entity class also overrides the **equality** operator (==) to easily check if two entities are equal (they are equals if they are same entity type and their Ids are equals).
+
+#### Entities with Composite Keys
+
+Some entities may need to have **composite keys**. In that case, you can derive your entity from the non-generic `Entity` class. Example:
+
+````C#
+public class UserRole : Entity
+{
+    public Guid UserId { get; set; }
+
+    public Guid RoleId { get; set; }
+    
+    public DateTime CreationTime { get; set; }
+
+    public Phone()
+    {
+            
+    }
+}
+````
+
+For the example above, the composite key is composed of `UserId` and `RoleId`. For a relational database, it is the composite primary key of the related table.
+
+> Composite primary keys has some restriction with repositories. Since it has not known Id property, you can not use `IRepository<TEntity, TKey>` for these entities. However, you can always use `IRepository<TEntity>`. See repository documentation (TODO: link) for more.
+
+### AggregateRoot Class
+
+"*Aggregate is a pattern in Domain-Driven Design. A DDD aggregate is a cluster of domain objects that can be treated as a single unit. An example may be an order and its line-items, these will be separate objects, but it's useful to treat the order (together with its line items) as a single aggregate.*" (see the [full description](http://martinfowler.com/bliki/DDD_Aggregate.html))
+
+`AggregateRoot` extends `Entity`. So, it also has an `Id` property by default. 
+
+> Notice that ABP creates default repositories only for aggregate roots by default. However, it's possible to include all entities. See repository documentation (TODO: link) for more. 
+
+ABP does not force you to use aggregate roots, you can only use the `Entity` class as defined before. However, if you want to implement DDD and want to create aggregate root classes, there are some best practices you can consider:
+
+* An aggregate root is responsible to preserve it's own integrity. This is also true for all entities, but aggregate root has responsibility for it's sub entities too.
+* An aggregate root can be referenced by it's Id. Do not reference it by navigation property.
+* An aggregate root is treated as a single unit. It's retrieved and updated as a single unit. It's generally considered as a transaction boundary.
+* Work with sub-entities over the aggregate root, do not modify them independently.
+
+#### Aggregate Example
+
+This is a full sample of an aggregate root with a related sub-entity collection:
+
+````C#
+public class Order : AggregateRoot<Guid>
+{
+    public virtual string ReferenceNo { get; protected set; }
+
+    public virtual int TotalItemCount { get; protected set; }
+
+    public virtual DateTime CreationTime { get; protected set; }
+
+    public virtual List<OrderLine> OrderLines { get; protected set; }
+
+    protected Order()
+    {
+
+    }
+
+    public Order(Guid id, string referenceNo)
+    {
+        Id = id;
+        ReferenceNo = referenceNo;
+        OrderLines = new List<OrderLine>();
+    }
+
+    public void AddProduct(Guid productId, int count)
+    {
+        if (count <= 0)
+        {
+            throw new ArgumentException(
+                "You can not add zero or negative count of products!",
+                nameof(count)
+            );
+        }
+
+        var existingLine = OrderLines.FirstOrDefault(ol => ol.ProductId == productId);
+
+        if (existingLine == null)
+        {
+            OrderLines.Add(new OrderLine(this.Id, productId, count));
+        }
+        else
+        {
+            existingLine.ChangeCount(existingLine.Count + count);
+        }
+
+        TotalItemCount += count;
+    }
+}
+
+public class OrderLine : Entity
+{
+    public virtual Guid OrderId { get; protected set; }
+
+    public virtual Guid ProductId { get; protected set; }
+
+    public virtual int Count { get; protected set; }
+
+    protected OrderLine()
+    {
+
+    }
+
+    internal OrderLine(Guid orderId, Guid productId, int count)
+    {
+        OrderId = orderId;
+        ProductId = productId;
+        Count = count;
+    }
+
+    internal void ChangeCount(int newCount)
+    {
+        Count = newCount;
+    }
+}
+````
+
+In this example;
+
+* `Order` is an **aggregate root entity** with `Guid` type `Id` property. It has a collection of `OrderLine` entities. `OrderLine` is another entity with a composite primary key (`OrderLine`  and ` ProductId`).
+* ...
+
diff --git a/src/Volo.Abp.Ddd/Microsoft/Extensions/DependencyInjection/ServiceCollectionRepositoryExtensions.cs b/src/Volo.Abp.Ddd/Microsoft/Extensions/DependencyInjection/ServiceCollectionRepositoryExtensions.cs
index 1e75094169..e6203386ae 100644
--- a/src/Volo.Abp.Ddd/Microsoft/Extensions/DependencyInjection/ServiceCollectionRepositoryExtensions.cs
+++ b/src/Volo.Abp.Ddd/Microsoft/Extensions/DependencyInjection/ServiceCollectionRepositoryExtensions.cs
@@ -31,14 +31,14 @@ namespace Microsoft.Extensions.DependencyInjection
 
             if (primaryKeyType != null)
             {
-                //IRepository<TEntity, TPrimaryKey>
+                //IRepository<TEntity, TKey>
                 var repositoryInterface = typeof(IRepository<,>).MakeGenericType(entityType, primaryKeyType);
                 if (repositoryInterface.GetTypeInfo().IsAssignableFrom(repositoryImplementationType))
                 {
                     services.TryAddTransient(repositoryInterface, repositoryImplementationType);
                 }
 
-                //IQueryableRepository<TEntity, TPrimaryKey>
+                //IQueryableRepository<TEntity, TKey>
                 var queryableRepositoryInterface = typeof(IQueryableRepository<,>).MakeGenericType(entityType, primaryKeyType);
                 if (queryableRepositoryInterface.GetTypeInfo().IsAssignableFrom(repositoryImplementationType))
                 {
diff --git a/src/Volo.Abp.Ddd/Volo/Abp/Application/Dtos/EntityDto.cs b/src/Volo.Abp.Ddd/Volo/Abp/Application/Dtos/EntityDto.cs
index aaf4e1da9a..76407cf8a5 100644
--- a/src/Volo.Abp.Ddd/Volo/Abp/Application/Dtos/EntityDto.cs
+++ b/src/Volo.Abp.Ddd/Volo/Abp/Application/Dtos/EntityDto.cs
@@ -8,15 +8,15 @@ namespace Volo.Abp.Application.Dtos
         }
     }
 
-    public class EntityDto<TPrimaryKey> : EntityDto, IEntityDto<TPrimaryKey>
+    public class EntityDto<TKey> : EntityDto, IEntityDto<TKey>
     {
         /// <summary>
         /// Id of the entity.
         /// </summary>
-        public TPrimaryKey Id { get; set; }
+        public TKey Id { get; set; }
 
         /// <summary>
-        /// Creates a new <see cref="EntityDto{TPrimaryKey}"/> object.
+        /// Creates a new <see cref="EntityDto{TKey}"/> object.
         /// </summary>
         public EntityDto()
         {
@@ -24,10 +24,10 @@ namespace Volo.Abp.Application.Dtos
         }
 
         /// <summary>
-        /// Creates a new <see cref="EntityDto{TPrimaryKey}"/> object.
+        /// Creates a new <see cref="EntityDto{TKey}"/> object.
         /// </summary>
         /// <param name="id">Id of the entity</param>
-        public EntityDto(TPrimaryKey id)
+        public EntityDto(TKey id)
         {
             Id = id;
         }
diff --git a/src/Volo.Abp.Ddd/Volo/Abp/Application/Dtos/IEntityDto.cs b/src/Volo.Abp.Ddd/Volo/Abp/Application/Dtos/IEntityDto.cs
index 00e0f98cdb..1f774e50d1 100644
--- a/src/Volo.Abp.Ddd/Volo/Abp/Application/Dtos/IEntityDto.cs
+++ b/src/Volo.Abp.Ddd/Volo/Abp/Application/Dtos/IEntityDto.cs
@@ -5,8 +5,8 @@
 
     }
 
-    public interface IEntityDto<TPrimaryKey> : IEntityDto
+    public interface IEntityDto<TKey> : IEntityDto
     {
-        TPrimaryKey Id { get; set; }
+        TKey Id { get; set; }
     }
 }
\ No newline at end of file
diff --git a/src/Volo.Abp.Ddd/Volo/Abp/Application/Services/AsyncCrudAppService.cs b/src/Volo.Abp.Ddd/Volo/Abp/Application/Services/AsyncCrudAppService.cs
index 2e631d2f4c..bbd4a8eaeb 100644
--- a/src/Volo.Abp.Ddd/Volo/Abp/Application/Services/AsyncCrudAppService.cs
+++ b/src/Volo.Abp.Ddd/Volo/Abp/Application/Services/AsyncCrudAppService.cs
@@ -7,59 +7,59 @@ using Volo.Abp.Linq;
 
 namespace Volo.Abp.Application.Services
 {
-    public abstract class AsyncCrudAppService<TEntity, TEntityDto, TPrimaryKey>
-        : AsyncCrudAppService<TEntity, TEntityDto, TPrimaryKey, PagedAndSortedResultRequestDto>
-        where TEntity : class, IEntity<TPrimaryKey>
-        where TEntityDto : IEntityDto<TPrimaryKey>
+    public abstract class AsyncCrudAppService<TEntity, TEntityDto, TKey>
+        : AsyncCrudAppService<TEntity, TEntityDto, TKey, PagedAndSortedResultRequestDto>
+        where TEntity : class, IEntity<TKey>
+        where TEntityDto : IEntityDto<TKey>
     {
-        protected AsyncCrudAppService(IQueryableRepository<TEntity, TPrimaryKey> repository)
+        protected AsyncCrudAppService(IQueryableRepository<TEntity, TKey> repository)
             : base(repository)
         {
 
         }
     }
 
-    public abstract class AsyncCrudAppService<TEntity, TEntityDto, TPrimaryKey, TGetAllInput>
-        : AsyncCrudAppService<TEntity, TEntityDto, TPrimaryKey, TGetAllInput, TEntityDto, TEntityDto>
-        where TEntity : class, IEntity<TPrimaryKey>
-        where TEntityDto : IEntityDto<TPrimaryKey>
+    public abstract class AsyncCrudAppService<TEntity, TEntityDto, TKey, TGetAllInput>
+        : AsyncCrudAppService<TEntity, TEntityDto, TKey, TGetAllInput, TEntityDto, TEntityDto>
+        where TEntity : class, IEntity<TKey>
+        where TEntityDto : IEntityDto<TKey>
     {
-        protected AsyncCrudAppService(IQueryableRepository<TEntity, TPrimaryKey> repository)
+        protected AsyncCrudAppService(IQueryableRepository<TEntity, TKey> repository)
             : base(repository)
         {
 
         }
     }
 
-    public abstract class AsyncCrudAppService<TEntity, TEntityDto, TPrimaryKey, TGetAllInput, TCreateInput>
-        : AsyncCrudAppService<TEntity, TEntityDto, TPrimaryKey, TGetAllInput, TCreateInput, TCreateInput>
+    public abstract class AsyncCrudAppService<TEntity, TEntityDto, TKey, TGetAllInput, TCreateInput>
+        : AsyncCrudAppService<TEntity, TEntityDto, TKey, TGetAllInput, TCreateInput, TCreateInput>
         where TGetAllInput : IPagedAndSortedResultRequest
-        where TEntity : class, IEntity<TPrimaryKey>
-        where TEntityDto : IEntityDto<TPrimaryKey>
-        where TCreateInput : IEntityDto<TPrimaryKey>
+        where TEntity : class, IEntity<TKey>
+        where TEntityDto : IEntityDto<TKey>
+        where TCreateInput : IEntityDto<TKey>
     {
-        protected AsyncCrudAppService(IQueryableRepository<TEntity, TPrimaryKey> repository)
+        protected AsyncCrudAppService(IQueryableRepository<TEntity, TKey> repository)
             : base(repository)
         {
 
         }
     }
 
-    public abstract class AsyncCrudAppService<TEntity, TEntityDto, TPrimaryKey, TGetAllInput, TCreateInput, TUpdateInput>
-       : CrudAppServiceBase<TEntity, TEntityDto, TPrimaryKey, TGetAllInput, TCreateInput, TUpdateInput>,
-        IAsyncCrudAppService<TEntityDto, TPrimaryKey, TGetAllInput, TCreateInput, TUpdateInput>
-           where TEntity : class, IEntity<TPrimaryKey>
-           where TEntityDto : IEntityDto<TPrimaryKey>
+    public abstract class AsyncCrudAppService<TEntity, TEntityDto, TKey, TGetAllInput, TCreateInput, TUpdateInput>
+       : CrudAppServiceBase<TEntity, TEntityDto, TKey, TGetAllInput, TCreateInput, TUpdateInput>,
+        IAsyncCrudAppService<TEntityDto, TKey, TGetAllInput, TCreateInput, TUpdateInput>
+           where TEntity : class, IEntity<TKey>
+           where TEntityDto : IEntityDto<TKey>
     {
         public IAsyncQueryableExecuter AsyncQueryableExecuter { get; set; }
 
-        protected AsyncCrudAppService(IQueryableRepository<TEntity, TPrimaryKey> repository)
+        protected AsyncCrudAppService(IQueryableRepository<TEntity, TKey> repository)
             :base(repository)
         {
             AsyncQueryableExecuter = DefaultAsyncQueryableExecuter.Instance;
         }
 
-        public virtual async Task<TEntityDto> GetAsync(TPrimaryKey id)
+        public virtual async Task<TEntityDto> GetAsync(TKey id)
         {
             CheckGetPermission();
 
@@ -98,7 +98,7 @@ namespace Volo.Abp.Application.Services
             return MapToEntityDto(entity);
         }
 
-        public virtual async Task<TEntityDto> UpdateAsync(TPrimaryKey id, TUpdateInput input)
+        public virtual async Task<TEntityDto> UpdateAsync(TKey id, TUpdateInput input)
         {
             CheckUpdatePermission();
 
@@ -112,14 +112,14 @@ namespace Volo.Abp.Application.Services
             return MapToEntityDto(entity);
         }
 
-        public virtual Task DeleteAsync(TPrimaryKey id)
+        public virtual Task DeleteAsync(TKey id)
         {
             CheckDeletePermission();
 
             return Repository.DeleteAsync(id);
         }
 
-        protected virtual Task<TEntity> GetEntityByIdAsync(TPrimaryKey id)
+        protected virtual Task<TEntity> GetEntityByIdAsync(TKey id)
         {
             return Repository.GetAsync(id);
         }
diff --git a/src/Volo.Abp.Ddd/Volo/Abp/Application/Services/CrudAppService.cs b/src/Volo.Abp.Ddd/Volo/Abp/Application/Services/CrudAppService.cs
index cec074f909..367552dba0 100644
--- a/src/Volo.Abp.Ddd/Volo/Abp/Application/Services/CrudAppService.cs
+++ b/src/Volo.Abp.Ddd/Volo/Abp/Application/Services/CrudAppService.cs
@@ -5,56 +5,56 @@ using Volo.Abp.Domain.Repositories;
 
 namespace Volo.Abp.Application.Services
 {
-    public abstract class CrudAppService<TEntity, TEntityDto, TPrimaryKey>
-        : CrudAppService<TEntity, TEntityDto, TPrimaryKey, PagedAndSortedResultRequestDto>
-        where TEntity : class, IEntity<TPrimaryKey>
-        where TEntityDto : IEntityDto<TPrimaryKey>
+    public abstract class CrudAppService<TEntity, TEntityDto, TKey>
+        : CrudAppService<TEntity, TEntityDto, TKey, PagedAndSortedResultRequestDto>
+        where TEntity : class, IEntity<TKey>
+        where TEntityDto : IEntityDto<TKey>
     {
-        protected CrudAppService(IQueryableRepository<TEntity, TPrimaryKey> repository)
+        protected CrudAppService(IQueryableRepository<TEntity, TKey> repository)
             : base(repository)
         {
 
         }
     }
 
-    public abstract class CrudAppService<TEntity, TEntityDto, TPrimaryKey, TGetAllInput>
-        : CrudAppService<TEntity, TEntityDto, TPrimaryKey, TGetAllInput, TEntityDto, TEntityDto>
-        where TEntity : class, IEntity<TPrimaryKey>
-        where TEntityDto : IEntityDto<TPrimaryKey>
+    public abstract class CrudAppService<TEntity, TEntityDto, TKey, TGetAllInput>
+        : CrudAppService<TEntity, TEntityDto, TKey, TGetAllInput, TEntityDto, TEntityDto>
+        where TEntity : class, IEntity<TKey>
+        where TEntityDto : IEntityDto<TKey>
     {
-        protected CrudAppService(IQueryableRepository<TEntity, TPrimaryKey> repository)
+        protected CrudAppService(IQueryableRepository<TEntity, TKey> repository)
             : base(repository)
         {
 
         }
     }
 
-    public abstract class CrudAppService<TEntity, TEntityDto, TPrimaryKey, TGetAllInput, TCreateInput>
-        : CrudAppService<TEntity, TEntityDto, TPrimaryKey, TGetAllInput, TCreateInput, TCreateInput>
-        where TEntity : class, IEntity<TPrimaryKey>
-        where TEntityDto : IEntityDto<TPrimaryKey>
-        where TCreateInput : IEntityDto<TPrimaryKey>
+    public abstract class CrudAppService<TEntity, TEntityDto, TKey, TGetAllInput, TCreateInput>
+        : CrudAppService<TEntity, TEntityDto, TKey, TGetAllInput, TCreateInput, TCreateInput>
+        where TEntity : class, IEntity<TKey>
+        where TEntityDto : IEntityDto<TKey>
+        where TCreateInput : IEntityDto<TKey>
     {
-        protected CrudAppService(IQueryableRepository<TEntity, TPrimaryKey> repository)
+        protected CrudAppService(IQueryableRepository<TEntity, TKey> repository)
             : base(repository)
         {
 
         }
     }
 
-    public abstract class CrudAppService<TEntity, TEntityDto, TPrimaryKey, TGetAllInput, TCreateInput, TUpdateInput>
-       : CrudAppServiceBase<TEntity, TEntityDto, TPrimaryKey, TGetAllInput, TCreateInput, TUpdateInput>,
-        ICrudAppService<TEntityDto, TPrimaryKey, TGetAllInput, TCreateInput, TUpdateInput>
-           where TEntity : class, IEntity<TPrimaryKey>
-           where TEntityDto : IEntityDto<TPrimaryKey>
+    public abstract class CrudAppService<TEntity, TEntityDto, TKey, TGetAllInput, TCreateInput, TUpdateInput>
+       : CrudAppServiceBase<TEntity, TEntityDto, TKey, TGetAllInput, TCreateInput, TUpdateInput>,
+        ICrudAppService<TEntityDto, TKey, TGetAllInput, TCreateInput, TUpdateInput>
+           where TEntity : class, IEntity<TKey>
+           where TEntityDto : IEntityDto<TKey>
     {
-        protected CrudAppService(IQueryableRepository<TEntity, TPrimaryKey> repository)
+        protected CrudAppService(IQueryableRepository<TEntity, TKey> repository)
             : base(repository)
         {
 
         }
 
-        public virtual TEntityDto Get(TPrimaryKey id)
+        public virtual TEntityDto Get(TKey id)
         {
             CheckGetPermission();
 
@@ -93,7 +93,7 @@ namespace Volo.Abp.Application.Services
             return MapToEntityDto(entity);
         }
 
-        public virtual TEntityDto Update(TPrimaryKey id, TUpdateInput input)
+        public virtual TEntityDto Update(TKey id, TUpdateInput input)
         {
             CheckUpdatePermission();
 
@@ -105,14 +105,14 @@ namespace Volo.Abp.Application.Services
             return MapToEntityDto(entity);
         }
 
-        public virtual void Delete(TPrimaryKey id)
+        public virtual void Delete(TKey id)
         {
             CheckDeletePermission();
 
             Repository.Delete(id);
         }
 
-        protected virtual TEntity GetEntityById(TPrimaryKey id)
+        protected virtual TEntity GetEntityById(TKey id)
         {
             return Repository.Get(id);
         }
diff --git a/src/Volo.Abp.Ddd/Volo/Abp/Application/Services/CrudAppServiceBase.cs b/src/Volo.Abp.Ddd/Volo/Abp/Application/Services/CrudAppServiceBase.cs
index ec04a532ab..b9ad25a574 100644
--- a/src/Volo.Abp.Ddd/Volo/Abp/Application/Services/CrudAppServiceBase.cs
+++ b/src/Volo.Abp.Ddd/Volo/Abp/Application/Services/CrudAppServiceBase.cs
@@ -11,11 +11,11 @@ namespace Volo.Abp.Application.Services
     /// This is a common base class for CrudAppService and AsyncCrudAppService classes.
     /// Inherit either from CrudAppService or AsyncCrudAppService, not from this class.
     /// </summary>
-    public abstract class CrudAppServiceBase<TEntity, TEntityDto, TPrimaryKey, TGetAllInput, TCreateInput, TUpdateInput> : ApplicationService
-        where TEntity : class, IEntity<TPrimaryKey>
-        where TEntityDto : IEntityDto<TPrimaryKey>
+    public abstract class CrudAppServiceBase<TEntity, TEntityDto, TKey, TGetAllInput, TCreateInput, TUpdateInput> : ApplicationService
+        where TEntity : class, IEntity<TKey>
+        where TEntityDto : IEntityDto<TKey>
     {
-        protected IQueryableRepository<TEntity, TPrimaryKey> Repository { get; }
+        protected IQueryableRepository<TEntity, TKey> Repository { get; }
         
         protected virtual string GetPermissionName { get; set; }
 
@@ -27,7 +27,7 @@ namespace Volo.Abp.Application.Services
 
         protected virtual string DeletePermissionName { get; set; }
 
-        protected CrudAppServiceBase(IQueryableRepository<TEntity, TPrimaryKey> repository)
+        protected CrudAppServiceBase(IQueryableRepository<TEntity, TKey> repository)
         {
             Repository = repository;
         }
@@ -119,7 +119,7 @@ namespace Volo.Abp.Application.Services
         }
 
         /// <summary>
-        /// Sets Id value for the entity if <see cref="TPrimaryKey"/> is <see cref="Guid"/>.
+        /// Sets Id value for the entity if <see cref="TKey"/> is <see cref="Guid"/>.
         /// It's used while creating a new entity.
         /// </summary>
         protected virtual void SetIdForGuids(TEntity entity)
diff --git a/src/Volo.Abp.Ddd/Volo/Abp/Application/Services/IAsyncCrudAppService.cs b/src/Volo.Abp.Ddd/Volo/Abp/Application/Services/IAsyncCrudAppService.cs
index 37c8293df4..4f97c49ae0 100644
--- a/src/Volo.Abp.Ddd/Volo/Abp/Application/Services/IAsyncCrudAppService.cs
+++ b/src/Volo.Abp.Ddd/Volo/Abp/Application/Services/IAsyncCrudAppService.cs
@@ -3,39 +3,39 @@ using Volo.Abp.Application.Dtos;
 
 namespace Volo.Abp.Application.Services
 {
-    public interface IAsyncCrudAppService<TEntityDto, in TPrimaryKey>
-        : IAsyncCrudAppService<TEntityDto, TPrimaryKey, PagedAndSortedResultRequestDto>
-        where TEntityDto : IEntityDto<TPrimaryKey>
+    public interface IAsyncCrudAppService<TEntityDto, in TKey>
+        : IAsyncCrudAppService<TEntityDto, TKey, PagedAndSortedResultRequestDto>
+        where TEntityDto : IEntityDto<TKey>
     {
 
     }
 
-    public interface IAsyncCrudAppService<TEntityDto, in TPrimaryKey, in TGetListInput>
-        : IAsyncCrudAppService<TEntityDto, TPrimaryKey, TGetListInput, TEntityDto, TEntityDto>
-        where TEntityDto : IEntityDto<TPrimaryKey>
+    public interface IAsyncCrudAppService<TEntityDto, in TKey, in TGetListInput>
+        : IAsyncCrudAppService<TEntityDto, TKey, TGetListInput, TEntityDto, TEntityDto>
+        where TEntityDto : IEntityDto<TKey>
     {
 
     }
 
-    public interface IAsyncCrudAppService<TEntityDto, in TPrimaryKey, in TGetListInput, in TCreateInput>
-        : IAsyncCrudAppService<TEntityDto, TPrimaryKey, TGetListInput, TCreateInput, TCreateInput>
-        where TEntityDto : IEntityDto<TPrimaryKey>
+    public interface IAsyncCrudAppService<TEntityDto, in TKey, in TGetListInput, in TCreateInput>
+        : IAsyncCrudAppService<TEntityDto, TKey, TGetListInput, TCreateInput, TCreateInput>
+        where TEntityDto : IEntityDto<TKey>
     {
 
     }
 
-    public interface IAsyncCrudAppService<TEntityDto, in TPrimaryKey, in TGetListInput, in TCreateInput, in TUpdateInput>
+    public interface IAsyncCrudAppService<TEntityDto, in TKey, in TGetListInput, in TCreateInput, in TUpdateInput>
         : IApplicationService
-        where TEntityDto : IEntityDto<TPrimaryKey>
+        where TEntityDto : IEntityDto<TKey>
     {
-        Task<TEntityDto> GetAsync(TPrimaryKey id);
+        Task<TEntityDto> GetAsync(TKey id);
 
         Task<PagedResultDto<TEntityDto>> GetListAsync(TGetListInput input);
 
         Task<TEntityDto> CreateAsync(TCreateInput input);
 
-        Task<TEntityDto> UpdateAsync(TPrimaryKey id, TUpdateInput input);
+        Task<TEntityDto> UpdateAsync(TKey id, TUpdateInput input);
 
-        Task DeleteAsync(TPrimaryKey id);
+        Task DeleteAsync(TKey id);
     }
 }
diff --git a/src/Volo.Abp.Ddd/Volo/Abp/Application/Services/ICrudAppService.cs b/src/Volo.Abp.Ddd/Volo/Abp/Application/Services/ICrudAppService.cs
index 9400f8825c..9f06c63aea 100644
--- a/src/Volo.Abp.Ddd/Volo/Abp/Application/Services/ICrudAppService.cs
+++ b/src/Volo.Abp.Ddd/Volo/Abp/Application/Services/ICrudAppService.cs
@@ -2,39 +2,39 @@ using Volo.Abp.Application.Dtos;
 
 namespace Volo.Abp.Application.Services
 {
-    public interface ICrudAppService<TEntityDto, in TPrimaryKey>
-        : ICrudAppService<TEntityDto, TPrimaryKey, PagedAndSortedResultRequestDto>
-        where TEntityDto : IEntityDto<TPrimaryKey>
+    public interface ICrudAppService<TEntityDto, in TKey>
+        : ICrudAppService<TEntityDto, TKey, PagedAndSortedResultRequestDto>
+        where TEntityDto : IEntityDto<TKey>
     {
 
     }
 
-    public interface ICrudAppService<TEntityDto, in TPrimaryKey, in TGetListInput>
-        : ICrudAppService<TEntityDto, TPrimaryKey, TGetListInput, TEntityDto, TEntityDto>
-        where TEntityDto : IEntityDto<TPrimaryKey>
+    public interface ICrudAppService<TEntityDto, in TKey, in TGetListInput>
+        : ICrudAppService<TEntityDto, TKey, TGetListInput, TEntityDto, TEntityDto>
+        where TEntityDto : IEntityDto<TKey>
     {
 
     }
 
-    public interface ICrudAppService<TEntityDto, in TPrimaryKey, in TGetListInput, in TCreateInput>
-        : ICrudAppService<TEntityDto, TPrimaryKey, TGetListInput, TCreateInput, TCreateInput>
-        where TEntityDto : IEntityDto<TPrimaryKey>
+    public interface ICrudAppService<TEntityDto, in TKey, in TGetListInput, in TCreateInput>
+        : ICrudAppService<TEntityDto, TKey, TGetListInput, TCreateInput, TCreateInput>
+        where TEntityDto : IEntityDto<TKey>
     {
 
     }
 
-    public interface ICrudAppService<TEntityDto, in TPrimaryKey, in TGetListInput, in TCreateInput, in TUpdateInput>
+    public interface ICrudAppService<TEntityDto, in TKey, in TGetListInput, in TCreateInput, in TUpdateInput>
         : IApplicationService
-        where TEntityDto : IEntityDto<TPrimaryKey>
+        where TEntityDto : IEntityDto<TKey>
     {
-        TEntityDto Get(TPrimaryKey id);
+        TEntityDto Get(TKey id);
 
         PagedResultDto<TEntityDto> GetAll(TGetListInput input);
 
         TEntityDto Create(TCreateInput input);
 
-        TEntityDto Update(TPrimaryKey id, TUpdateInput input);
+        TEntityDto Update(TKey id, TUpdateInput input);
 
-        void Delete(TPrimaryKey id);
+        void Delete(TKey id);
     }
 }
diff --git a/src/Volo.Abp.Ddd/Volo/Abp/DependencyInjection/CommonDbContextRegistrationOptions.cs b/src/Volo.Abp.Ddd/Volo/Abp/DependencyInjection/CommonDbContextRegistrationOptions.cs
index e195a348bf..917e9bd57a 100644
--- a/src/Volo.Abp.Ddd/Volo/Abp/DependencyInjection/CommonDbContextRegistrationOptions.cs
+++ b/src/Volo.Abp.Ddd/Volo/Abp/DependencyInjection/CommonDbContextRegistrationOptions.cs
@@ -19,7 +19,7 @@ namespace Volo.Abp.DependencyInjection
 
         public Type DefaultRepositoryImplementationType { get; private set; }
 
-        public Type DefaultRepositoryImplementationTypeWithoutPrimaryKey { get; private set; }
+        public Type DefaultRepositoryImplementationTypeWithouTKey { get; private set; }
 
         public bool RegisterDefaultRepositories { get; private set; }
 
@@ -27,7 +27,7 @@ namespace Volo.Abp.DependencyInjection
 
         public Dictionary<Type, Type> CustomRepositories { get; }
 
-        public bool SpecifiedDefaultRepositoryTypes => DefaultRepositoryImplementationType != null && DefaultRepositoryImplementationTypeWithoutPrimaryKey != null;
+        public bool SpecifiedDefaultRepositoryTypes => DefaultRepositoryImplementationType != null && DefaultRepositoryImplementationTypeWithouTKey != null;
 
         protected CommonDbContextRegistrationOptions(Type originalDbContextType)
         {
@@ -88,14 +88,14 @@ namespace Volo.Abp.DependencyInjection
 
         public ICommonDbContextRegistrationOptionsBuilder SetDefaultRepositoryClasses(
             Type repositoryImplementationType,
-            Type repositoryImplementationTypeWithoutPrimaryKey
+            Type repositoryImplementationTypeWithouTKey
             )
         {
             Check.NotNull(repositoryImplementationType, nameof(repositoryImplementationType));
-            Check.NotNull(repositoryImplementationTypeWithoutPrimaryKey, nameof(repositoryImplementationTypeWithoutPrimaryKey));
+            Check.NotNull(repositoryImplementationTypeWithouTKey, nameof(repositoryImplementationTypeWithouTKey));
 
             DefaultRepositoryImplementationType = repositoryImplementationType;
-            DefaultRepositoryImplementationTypeWithoutPrimaryKey = repositoryImplementationTypeWithoutPrimaryKey;
+            DefaultRepositoryImplementationTypeWithouTKey = repositoryImplementationTypeWithouTKey;
 
             return this;
         }
diff --git a/src/Volo.Abp.Ddd/Volo/Abp/DependencyInjection/ICommonDbContextRegistrationOptionsBuilder.cs b/src/Volo.Abp.Ddd/Volo/Abp/DependencyInjection/ICommonDbContextRegistrationOptionsBuilder.cs
index c68b544ce2..837f7bc110 100644
--- a/src/Volo.Abp.Ddd/Volo/Abp/DependencyInjection/ICommonDbContextRegistrationOptionsBuilder.cs
+++ b/src/Volo.Abp.Ddd/Volo/Abp/DependencyInjection/ICommonDbContextRegistrationOptionsBuilder.cs
@@ -48,9 +48,9 @@ namespace Volo.Abp.DependencyInjection
         /// Uses given class(es) for default repositories.
         /// </summary>
         /// <param name="repositoryImplementationType">Repository implementation type</param>
-        /// <param name="repositoryImplementationTypeWithoutPrimaryKey">Repository implementation type (without primary key)</param>
+        /// <param name="repositoryImplementationTypeWithouTKey">Repository implementation type (without primary key)</param>
         /// <returns></returns>
-        ICommonDbContextRegistrationOptionsBuilder SetDefaultRepositoryClasses([NotNull] Type repositoryImplementationType, [NotNull] Type repositoryImplementationTypeWithoutPrimaryKey);
+        ICommonDbContextRegistrationOptionsBuilder SetDefaultRepositoryClasses([NotNull] Type repositoryImplementationType, [NotNull] Type repositoryImplementationTypeWithouTKey);
 
         /// <summary>
         /// Replaces given DbContext type with this DbContext type.
diff --git a/src/Volo.Abp.Ddd/Volo/Abp/Domain/Entities/AggregateRoot.cs b/src/Volo.Abp.Ddd/Volo/Abp/Domain/Entities/AggregateRoot.cs
index 65853729d6..a2b233406f 100644
--- a/src/Volo.Abp.Ddd/Volo/Abp/Domain/Entities/AggregateRoot.cs
+++ b/src/Volo.Abp.Ddd/Volo/Abp/Domain/Entities/AggregateRoot.cs
@@ -7,8 +7,8 @@
 
     }
 
-    /// <inheritdoc cref="IAggregateRoot{TPrimaryKey}" />
-    public abstract class AggregateRoot<TPrimaryKey> : Entity<TPrimaryKey>, IAggregateRoot<TPrimaryKey>
+    /// <inheritdoc cref="IAggregateRoot{TKey}" />
+    public abstract class AggregateRoot<TKey> : Entity<TKey>, IAggregateRoot<TKey>
     {
 
     }
diff --git a/src/Volo.Abp.Ddd/Volo/Abp/Domain/Entities/Entity.cs b/src/Volo.Abp.Ddd/Volo/Abp/Domain/Entities/Entity.cs
index 185aad9767..007442f781 100644
--- a/src/Volo.Abp.Ddd/Volo/Abp/Domain/Entities/Entity.cs
+++ b/src/Volo.Abp.Ddd/Volo/Abp/Domain/Entities/Entity.cs
@@ -12,16 +12,16 @@ namespace Volo.Abp.Domain.Entities
         }
     }
 
-    /// <inheritdoc cref="IEntity{TPrimaryKey}" />
-    public abstract class Entity<TPrimaryKey> : Entity, IEntity<TPrimaryKey>
+    /// <inheritdoc cref="IEntity{TKey}" />
+    public abstract class Entity<TKey> : Entity, IEntity<TKey>
     {
         /// <inheritdoc/>
-        public virtual TPrimaryKey Id { get; set; }
+        public virtual TKey Id { get; set; }
 
         /// <inheritdoc/>
         public override bool Equals(object obj)
         {
-            if (obj == null || !(obj is Entity<TPrimaryKey>))
+            if (obj == null || !(obj is Entity<TKey>))
             {
                 return false;
             }
@@ -33,7 +33,7 @@ namespace Volo.Abp.Domain.Entities
             }
 
             //Transient objects are not considered as equal
-            var other = (Entity<TPrimaryKey>)obj;
+            var other = (Entity<TKey>)obj;
             if (EntityHelper.IsTransient(this) && EntityHelper.IsTransient(other))
             {
                 return false;
@@ -61,7 +61,7 @@ namespace Volo.Abp.Domain.Entities
             return Id.GetHashCode();
         }
 
-        public static bool operator ==(Entity<TPrimaryKey> left, Entity<TPrimaryKey> right)
+        public static bool operator ==(Entity<TKey> left, Entity<TKey> right)
         {
             if (Equals(left, null))
             {
@@ -71,7 +71,7 @@ namespace Volo.Abp.Domain.Entities
             return left.Equals(right);
         }
 
-        public static bool operator !=(Entity<TPrimaryKey> left, Entity<TPrimaryKey> right)
+        public static bool operator !=(Entity<TKey> left, Entity<TKey> right)
         {
             return !(left == right);
         }
diff --git a/src/Volo.Abp.Ddd/Volo/Abp/Domain/Entities/EntityHelper.cs b/src/Volo.Abp.Ddd/Volo/Abp/Domain/Entities/EntityHelper.cs
index 3dee5b0ee5..18f6f2a8e9 100644
--- a/src/Volo.Abp.Ddd/Volo/Abp/Domain/Entities/EntityHelper.cs
+++ b/src/Volo.Abp.Ddd/Volo/Abp/Domain/Entities/EntityHelper.cs
@@ -16,20 +16,20 @@ namespace Volo.Abp.Domain.Entities
             return typeof(IEntity).IsAssignableFrom(type);
         }
 
-        public static bool IsTransient<TPrimaryKey>(IEntity<TPrimaryKey> entity) // TODO: Completely remove IsTransient
+        public static bool IsTransient<TKey>(IEntity<TKey> entity) // TODO: Completely remove IsTransient
         {
-            if (EqualityComparer<TPrimaryKey>.Default.Equals(entity.Id, default))
+            if (EqualityComparer<TKey>.Default.Equals(entity.Id, default))
             {
                 return true;
             }
 
             //Workaround for EF Core since it sets int/long to min value when attaching to dbcontext
-            if (typeof(TPrimaryKey) == typeof(int))
+            if (typeof(TKey) == typeof(int))
             {
                 return Convert.ToInt32(entity.Id) <= 0;
             }
 
-            if (typeof(TPrimaryKey) == typeof(long))
+            if (typeof(TKey) == typeof(long))
             {
                 return Convert.ToInt64(entity.Id) <= 0;
             }
@@ -39,7 +39,7 @@ namespace Volo.Abp.Domain.Entities
 
         /// <summary>
         /// Tries to find the primary key type of the given entity type.
-        /// May return null if given type does not implement <see cref="IEntity{TPrimaryKey}"/>
+        /// May return null if given type does not implement <see cref="IEntity{TKey}"/>
         /// </summary>
         [CanBeNull]
         public static Type FindPrimaryKeyType<TEntity>()
@@ -50,7 +50,7 @@ namespace Volo.Abp.Domain.Entities
 
         /// <summary>
         /// Tries to find the primary key type of the given entity type.
-        /// May return null if given type does not implement <see cref="IEntity{TPrimaryKey}"/>
+        /// May return null if given type does not implement <see cref="IEntity{TKey}"/>
         /// </summary>
         [CanBeNull]
         public static Type FindPrimaryKeyType([NotNull] Type entityType)
@@ -71,13 +71,13 @@ namespace Volo.Abp.Domain.Entities
             return null;
         }
 
-        public static Expression<Func<TEntity, bool>> CreateEqualityExpressionForId<TEntity, TPrimaryKey>(TPrimaryKey id)
-            where TEntity : IEntity<TPrimaryKey>
+        public static Expression<Func<TEntity, bool>> CreateEqualityExpressionForId<TEntity, TKey>(TKey id)
+            where TEntity : IEntity<TKey>
         {
             var lambdaParam = Expression.Parameter(typeof(TEntity));
             var lambdaBody = Expression.Equal(
                 Expression.PropertyOrField(lambdaParam, "Id"),
-                Expression.Constant(id, typeof(TPrimaryKey))
+                Expression.Constant(id, typeof(TKey))
             );
 
             return Expression.Lambda<Func<TEntity, bool>>(lambdaBody, lambdaParam);
diff --git a/src/Volo.Abp.Ddd/Volo/Abp/Domain/Entities/IAggregateRoot.cs b/src/Volo.Abp.Ddd/Volo/Abp/Domain/Entities/IAggregateRoot.cs
index 5050df0cca..bdb436c51d 100644
--- a/src/Volo.Abp.Ddd/Volo/Abp/Domain/Entities/IAggregateRoot.cs
+++ b/src/Volo.Abp.Ddd/Volo/Abp/Domain/Entities/IAggregateRoot.cs
@@ -2,7 +2,7 @@
 {
     /// <summary>
     /// Defines an aggregate root. It's primary key may not be "Id" or it may have a composite primary key.
-    /// Use <see cref="IAggregateRoot{TPrimaryKey}"/> where possible for better integration to repositories and other structures in the framework.
+    /// Use <see cref="IAggregateRoot{TKey}"/> where possible for better integration to repositories and other structures in the framework.
     /// </summary>
     public interface IAggregateRoot : IEntity
     {
@@ -12,8 +12,8 @@
     /// <summary>
     /// Defines an aggregate root with a single primary key with "Id" property.
     /// </summary>
-    /// <typeparam name="TPrimaryKey">Type of the primary key of the entity</typeparam>
-    public interface IAggregateRoot<TPrimaryKey> : IEntity<TPrimaryKey>, IAggregateRoot
+    /// <typeparam name="TKey">Type of the primary key of the entity</typeparam>
+    public interface IAggregateRoot<TKey> : IEntity<TKey>, IAggregateRoot
     {
 
     }
diff --git a/src/Volo.Abp.Ddd/Volo/Abp/Domain/Entities/IEntity.cs b/src/Volo.Abp.Ddd/Volo/Abp/Domain/Entities/IEntity.cs
index a2f17e3f82..4cc25837d1 100644
--- a/src/Volo.Abp.Ddd/Volo/Abp/Domain/Entities/IEntity.cs
+++ b/src/Volo.Abp.Ddd/Volo/Abp/Domain/Entities/IEntity.cs
@@ -2,7 +2,7 @@
 {
     /// <summary>
     /// Defines an entity. It's primary key may not be "Id" or it mah have a composite primary key.
-    /// Use <see cref="IEntity{TPrimaryKey}"/> where possible for better integration to repositories and other structures in the framework.
+    /// Use <see cref="IEntity{TKey}"/> where possible for better integration to repositories and other structures in the framework.
     /// </summary>
     public interface IEntity
     {
@@ -12,12 +12,12 @@
     /// <summary>
     /// Defines an entity with a single primary key with "Id" property.
     /// </summary>
-    /// <typeparam name="TPrimaryKey">Type of the primary key of the entity</typeparam>
-    public interface IEntity<TPrimaryKey> : IEntity
+    /// <typeparam name="TKey">Type of the primary key of the entity</typeparam>
+    public interface IEntity<TKey> : IEntity
     {
         /// <summary>
         /// Unique identifier for this entity.
         /// </summary>
-        TPrimaryKey Id { get; set; }
+        TKey Id { get; set; }
     }
 }
diff --git a/src/Volo.Abp.Ddd/Volo/Abp/Domain/Repositories/IQueryableRepository.cs b/src/Volo.Abp.Ddd/Volo/Abp/Domain/Repositories/IQueryableRepository.cs
index 6a0e35e4ed..52014849ad 100644
--- a/src/Volo.Abp.Ddd/Volo/Abp/Domain/Repositories/IQueryableRepository.cs
+++ b/src/Volo.Abp.Ddd/Volo/Abp/Domain/Repositories/IQueryableRepository.cs
@@ -31,8 +31,8 @@ namespace Volo.Abp.Domain.Repositories
         Task DeleteAsync([NotNull] Expression<Func<TEntity, bool>> predicate, CancellationToken cancellationToken = default);
     }
 
-    public interface IQueryableRepository<TEntity, TPrimaryKey> : IQueryableRepository<TEntity>, IRepository<TEntity, TPrimaryKey>
-        where TEntity : class, IEntity<TPrimaryKey>
+    public interface IQueryableRepository<TEntity, TKey> : IQueryableRepository<TEntity>, IRepository<TEntity, TKey>
+        where TEntity : class, IEntity<TKey>
     {
     }
 }
\ No newline at end of file
diff --git a/src/Volo.Abp.Ddd/Volo/Abp/Domain/Repositories/IRepository.cs b/src/Volo.Abp.Ddd/Volo/Abp/Domain/Repositories/IRepository.cs
index 1b70ff510f..94521c7628 100644
--- a/src/Volo.Abp.Ddd/Volo/Abp/Domain/Repositories/IRepository.cs
+++ b/src/Volo.Abp.Ddd/Volo/Abp/Domain/Repositories/IRepository.cs
@@ -69,8 +69,8 @@ namespace Volo.Abp.Domain.Repositories
         Task DeleteAsync([NotNull] TEntity entity, CancellationToken cancellationToken = default); //TODO: Return true if deleted
     }
 
-    public interface IRepository<TEntity, TPrimaryKey> : IRepository<TEntity>
-        where TEntity : class, IEntity<TPrimaryKey>
+    public interface IRepository<TEntity, TKey> : IRepository<TEntity>
+        where TEntity : class, IEntity<TKey>
     {
         /// <summary>
         /// Gets an entity with given primary key.
@@ -79,7 +79,7 @@ namespace Volo.Abp.Domain.Repositories
         /// <param name="id">Primary key of the entity to get</param>
         /// <returns>Entity</returns>
         [NotNull]
-        TEntity Get(TPrimaryKey id);
+        TEntity Get(TKey id);
 
         /// <summary>
         /// Gets an entity with given primary key.
@@ -89,7 +89,7 @@ namespace Volo.Abp.Domain.Repositories
         /// <param name="cancellationToken">A <see cref="T:System.Threading.CancellationToken" /> to observe while waiting for the task to complete.</param>
         /// <returns>Entity</returns>
         [NotNull]
-        Task<TEntity> GetAsync(TPrimaryKey id, CancellationToken cancellationToken = default);
+        Task<TEntity> GetAsync(TKey id, CancellationToken cancellationToken = default);
 
         /// <summary>
         /// Gets an entity with given primary key or null if not found.
@@ -97,7 +97,7 @@ namespace Volo.Abp.Domain.Repositories
         /// <param name="id">Primary key of the entity to get</param>
         /// <returns>Entity or null</returns>
         [CanBeNull]
-        TEntity Find(TPrimaryKey id);
+        TEntity Find(TKey id);
 
         /// <summary>
         /// Gets an entity with given primary key or null if not found.
@@ -105,19 +105,19 @@ namespace Volo.Abp.Domain.Repositories
         /// <param name="id">Primary key of the entity to get</param>
         /// <param name="cancellationToken">A <see cref="T:System.Threading.CancellationToken" /> to observe while waiting for the task to complete.</param>
         /// <returns>Entity or null</returns>
-        Task<TEntity> FindAsync(TPrimaryKey id, CancellationToken cancellationToken = default);
+        Task<TEntity> FindAsync(TKey id, CancellationToken cancellationToken = default);
 
         /// <summary>
         /// Deletes an entity by primary key.
         /// </summary>
         /// <param name="id">Primary key of the entity</param>
-        void Delete(TPrimaryKey id); //TODO: Return true if deleted
+        void Delete(TKey id); //TODO: Return true if deleted
 
         /// <summary>
         /// Deletes an entity by primary key.
         /// </summary>
         /// <param name="cancellationToken">A <see cref="T:System.Threading.CancellationToken" /> to observe while waiting for the task to complete.</param>
         /// <param name="id">Primary key of the entity</param>
-        Task DeleteAsync(TPrimaryKey id, CancellationToken cancellationToken = default);  //TODO: Return true if deleted
+        Task DeleteAsync(TKey id, CancellationToken cancellationToken = default);  //TODO: Return true if deleted
     }
 }
diff --git a/src/Volo.Abp.Ddd/Volo/Abp/Domain/Repositories/ISupportsExplicitLoading.cs b/src/Volo.Abp.Ddd/Volo/Abp/Domain/Repositories/ISupportsExplicitLoading.cs
index 9b4a98863c..79eb68daf6 100644
--- a/src/Volo.Abp.Ddd/Volo/Abp/Domain/Repositories/ISupportsExplicitLoading.cs
+++ b/src/Volo.Abp.Ddd/Volo/Abp/Domain/Repositories/ISupportsExplicitLoading.cs
@@ -7,8 +7,8 @@ using Volo.Abp.Domain.Entities;
 
 namespace Volo.Abp.Domain.Repositories
 {
-    public interface ISupportsExplicitLoading<TEntity, TPrimaryKey>
-        where TEntity : class, IEntity<TPrimaryKey>
+    public interface ISupportsExplicitLoading<TEntity, TKey>
+        where TEntity : class, IEntity<TKey>
     {
         Task EnsureCollectionLoadedAsync<TProperty>(
             TEntity entity,
diff --git a/src/Volo.Abp.Ddd/Volo/Abp/Domain/Repositories/QueryableRepositoryBase.cs b/src/Volo.Abp.Ddd/Volo/Abp/Domain/Repositories/QueryableRepositoryBase.cs
index 00ef2c07be..f7000714e0 100644
--- a/src/Volo.Abp.Ddd/Volo/Abp/Domain/Repositories/QueryableRepositoryBase.cs
+++ b/src/Volo.Abp.Ddd/Volo/Abp/Domain/Repositories/QueryableRepositoryBase.cs
@@ -68,15 +68,15 @@ namespace Volo.Abp.Domain.Repositories
         }
     }
 
-    public abstract class QueryableRepositoryBase<TEntity, TPrimaryKey> : QueryableRepositoryBase<TEntity>, IQueryableRepository<TEntity, TPrimaryKey>
-        where TEntity : class, IEntity<TPrimaryKey>
+    public abstract class QueryableRepositoryBase<TEntity, TKey> : QueryableRepositoryBase<TEntity>, IQueryableRepository<TEntity, TKey>
+        where TEntity : class, IEntity<TKey>
     {
-        public virtual TEntity Find(TPrimaryKey id)
+        public virtual TEntity Find(TKey id)
         {
-            return GetQueryable().FirstOrDefault(EntityHelper.CreateEqualityExpressionForId<TEntity, TPrimaryKey>(id));
+            return GetQueryable().FirstOrDefault(EntityHelper.CreateEqualityExpressionForId<TEntity, TKey>(id));
         }
 
-        public virtual TEntity Get(TPrimaryKey id)
+        public virtual TEntity Get(TKey id)
         {
             var entity = Find(id);
 
@@ -88,17 +88,17 @@ namespace Volo.Abp.Domain.Repositories
             return entity;
         }
 
-        public virtual Task<TEntity> GetAsync(TPrimaryKey id, CancellationToken cancellationToken = default)
+        public virtual Task<TEntity> GetAsync(TKey id, CancellationToken cancellationToken = default)
         {
             return Task.FromResult(Get(id));
         }
 
-        public virtual Task<TEntity> FindAsync(TPrimaryKey id, CancellationToken cancellationToken = default)
+        public virtual Task<TEntity> FindAsync(TKey id, CancellationToken cancellationToken = default)
         {
             return Task.FromResult(Find(id));
         }
 
-        public virtual void Delete(TPrimaryKey id)
+        public virtual void Delete(TKey id)
         {
             var entity = Find(id);
             if (entity == null)
@@ -109,7 +109,7 @@ namespace Volo.Abp.Domain.Repositories
             Delete(entity);
         }
 
-        public virtual Task DeleteAsync(TPrimaryKey id, CancellationToken cancellationToken = default)
+        public virtual Task DeleteAsync(TKey id, CancellationToken cancellationToken = default)
         {
             Delete(id);
             return Task.CompletedTask;
diff --git a/src/Volo.Abp.Ddd/Volo/Abp/Domain/Repositories/RepositoryBase.cs b/src/Volo.Abp.Ddd/Volo/Abp/Domain/Repositories/RepositoryBase.cs
index bc52a145a8..953b967c2c 100644
--- a/src/Volo.Abp.Ddd/Volo/Abp/Domain/Repositories/RepositoryBase.cs
+++ b/src/Volo.Abp.Ddd/Volo/Abp/Domain/Repositories/RepositoryBase.cs
@@ -43,10 +43,10 @@ namespace Volo.Abp.Domain.Repositories
         }
     }
 
-    public abstract class RepositoryBase<TEntity, TPrimaryKey> : RepositoryBase<TEntity>, IRepository<TEntity, TPrimaryKey>
-        where TEntity : class, IEntity<TPrimaryKey>
+    public abstract class RepositoryBase<TEntity, TKey> : RepositoryBase<TEntity>, IRepository<TEntity, TKey>
+        where TEntity : class, IEntity<TKey>
     {
-        public virtual TEntity Get(TPrimaryKey id)
+        public virtual TEntity Get(TKey id)
         {
             var entity = Find(id);
 
@@ -58,19 +58,19 @@ namespace Volo.Abp.Domain.Repositories
             return entity;
         }
 
-        public virtual Task<TEntity> GetAsync(TPrimaryKey id, CancellationToken cancellationToken = default)
+        public virtual Task<TEntity> GetAsync(TKey id, CancellationToken cancellationToken = default)
         {
             return Task.FromResult(Get(id));
         }
 
-        public abstract TEntity Find(TPrimaryKey id);
+        public abstract TEntity Find(TKey id);
 
-        public virtual Task<TEntity> FindAsync(TPrimaryKey id, CancellationToken cancellationToken = default)
+        public virtual Task<TEntity> FindAsync(TKey id, CancellationToken cancellationToken = default)
         {
             return Task.FromResult(Find(id));
         }
 
-        public virtual void Delete(TPrimaryKey id)
+        public virtual void Delete(TKey id)
         {
             var entity = Find(id);
             if (entity == null)
@@ -81,7 +81,7 @@ namespace Volo.Abp.Domain.Repositories
             Delete(entity);
         }
 
-        public virtual Task DeleteAsync(TPrimaryKey id, CancellationToken cancellationToken = default)
+        public virtual Task DeleteAsync(TKey id, CancellationToken cancellationToken = default)
         {
             Delete(id);
             return Task.CompletedTask;
diff --git a/src/Volo.Abp.Ddd/Volo/Abp/Domain/Repositories/RepositoryExtensions.cs b/src/Volo.Abp.Ddd/Volo/Abp/Domain/Repositories/RepositoryExtensions.cs
index 3c9a503780..ccb4cd2c60 100644
--- a/src/Volo.Abp.Ddd/Volo/Abp/Domain/Repositories/RepositoryExtensions.cs
+++ b/src/Volo.Abp.Ddd/Volo/Abp/Domain/Repositories/RepositoryExtensions.cs
@@ -11,55 +11,55 @@ namespace Volo.Abp.Domain.Repositories
 {
     public static class RepositoryExtensions
     {
-        public static async Task EnsureCollectionLoadedAsync<TEntity, TPrimaryKey, TProperty>(
-            this IRepository<TEntity, TPrimaryKey> repository,
+        public static async Task EnsureCollectionLoadedAsync<TEntity, TKey, TProperty>(
+            this IRepository<TEntity, TKey> repository,
             TEntity entity,
             Expression<Func<TEntity, IEnumerable<TProperty>>> propertyExpression,
             CancellationToken cancellationToken = default
         )
-            where TEntity : class, IEntity<TPrimaryKey>
+            where TEntity : class, IEntity<TKey>
             where TProperty : class
         {
-            var repo = ProxyHelper.UnProxy(repository) as ISupportsExplicitLoading<TEntity, TPrimaryKey>;
+            var repo = ProxyHelper.UnProxy(repository) as ISupportsExplicitLoading<TEntity, TKey>;
             if (repo != null)
             {
                 await repo.EnsureCollectionLoadedAsync(entity, propertyExpression, cancellationToken);
             }
         }
 
-        public static void EnsureCollectionLoaded<TEntity, TPrimaryKey, TProperty>(
-            this IRepository<TEntity, TPrimaryKey> repository,
+        public static void EnsureCollectionLoaded<TEntity, TKey, TProperty>(
+            this IRepository<TEntity, TKey> repository,
             TEntity entity,
             Expression<Func<TEntity, IEnumerable<TProperty>>> propertyExpression
         )
-            where TEntity : class, IEntity<TPrimaryKey>
+            where TEntity : class, IEntity<TKey>
             where TProperty : class
         {
             AsyncHelper.RunSync(() => repository.EnsureCollectionLoadedAsync(entity, propertyExpression));
         }
 
-        public static async Task EnsurePropertyLoadedAsync<TEntity, TPrimaryKey, TProperty>(
-            this IRepository<TEntity, TPrimaryKey> repository,
+        public static async Task EnsurePropertyLoadedAsync<TEntity, TKey, TProperty>(
+            this IRepository<TEntity, TKey> repository,
             TEntity entity,
             Expression<Func<TEntity, TProperty>> propertyExpression,
             CancellationToken cancellationToken = default
         )
-            where TEntity : class, IEntity<TPrimaryKey>
+            where TEntity : class, IEntity<TKey>
             where TProperty : class
         {
-            var repo = ProxyHelper.UnProxy(repository) as ISupportsExplicitLoading<TEntity, TPrimaryKey>;
+            var repo = ProxyHelper.UnProxy(repository) as ISupportsExplicitLoading<TEntity, TKey>;
             if (repo != null)
             {
                 await repo.EnsurePropertyLoadedAsync(entity, propertyExpression, cancellationToken);
             }
         }
 
-        public static void EnsurePropertyLoaded<TEntity, TPrimaryKey, TProperty>(
-            this IRepository<TEntity, TPrimaryKey> repository,
+        public static void EnsurePropertyLoaded<TEntity, TKey, TProperty>(
+            this IRepository<TEntity, TKey> repository,
             TEntity entity,
             Expression<Func<TEntity, TProperty>> propertyExpression
         )
-            where TEntity : class, IEntity<TPrimaryKey>
+            where TEntity : class, IEntity<TKey>
             where TProperty : class
         {
             AsyncHelper.RunSync(() => repository.EnsurePropertyLoadedAsync(entity, propertyExpression));
diff --git a/src/Volo.Abp.Ddd/Volo/Abp/Domain/Repositories/RepositoryRegistrarBase.cs b/src/Volo.Abp.Ddd/Volo/Abp/Domain/Repositories/RepositoryRegistrarBase.cs
index 9b5510de89..addae8de35 100644
--- a/src/Volo.Abp.Ddd/Volo/Abp/Domain/Repositories/RepositoryRegistrarBase.cs
+++ b/src/Volo.Abp.Ddd/Volo/Abp/Domain/Repositories/RepositoryRegistrarBase.cs
@@ -57,7 +57,7 @@ namespace Volo.Abp.Domain.Repositories
             if (primaryKeyType == null)
             {
                 return Options.SpecifiedDefaultRepositoryTypes
-                    ? Options.DefaultRepositoryImplementationTypeWithoutPrimaryKey.MakeGenericType(entityType)
+                    ? Options.DefaultRepositoryImplementationTypeWithouTKey.MakeGenericType(entityType)
                     : GetRepositoryType(Options.DefaultRepositoryDbContextType, entityType);
             }
 
diff --git a/src/Volo.Abp.EntityFrameworkCore/Volo/Abp/Domain/Repositories/EfCoreRepositoryExtensions.cs b/src/Volo.Abp.EntityFrameworkCore/Volo/Abp/Domain/Repositories/EfCoreRepositoryExtensions.cs
index 84471504f7..33f34a79bf 100644
--- a/src/Volo.Abp.EntityFrameworkCore/Volo/Abp/Domain/Repositories/EfCoreRepositoryExtensions.cs
+++ b/src/Volo.Abp.EntityFrameworkCore/Volo/Abp/Domain/Repositories/EfCoreRepositoryExtensions.cs
@@ -7,25 +7,25 @@ namespace Volo.Abp.Domain.Repositories
 {
     public static class EfCoreRepositoryExtensions
     {
-        public static DbContext GetDbContext<TEntity, TPrimaryKey>(this IRepository<TEntity, TPrimaryKey> repository)
-            where TEntity : class, IEntity<TPrimaryKey>
+        public static DbContext GetDbContext<TEntity, TKey>(this IRepository<TEntity, TKey> repository)
+            where TEntity : class, IEntity<TKey>
         {
             return repository.ToEfCoreRepository().DbContext;
         }
 
-        public static DbSet<TEntity> GetDbSet<TEntity, TPrimaryKey>(this IRepository<TEntity, TPrimaryKey> repository)
-            where TEntity : class, IEntity<TPrimaryKey>
+        public static DbSet<TEntity> GetDbSet<TEntity, TKey>(this IRepository<TEntity, TKey> repository)
+            where TEntity : class, IEntity<TKey>
         {
             return repository.ToEfCoreRepository().DbSet;
         }
 
-        public static IEfCoreRepository<TEntity, TPrimaryKey> ToEfCoreRepository<TEntity, TPrimaryKey>(this IRepository<TEntity, TPrimaryKey> repository)
-            where TEntity : class, IEntity<TPrimaryKey>
+        public static IEfCoreRepository<TEntity, TKey> ToEfCoreRepository<TEntity, TKey>(this IRepository<TEntity, TKey> repository)
+            where TEntity : class, IEntity<TKey>
         {
-            var efCoreRepository = repository as IEfCoreRepository<TEntity, TPrimaryKey>;
+            var efCoreRepository = repository as IEfCoreRepository<TEntity, TKey>;
             if (efCoreRepository == null)
             {
-                throw new ArgumentException("Given repository does not implement " + typeof(IEfCoreRepository<TEntity, TPrimaryKey>).AssemblyQualifiedName, nameof(repository));
+                throw new ArgumentException("Given repository does not implement " + typeof(IEfCoreRepository<TEntity, TKey>).AssemblyQualifiedName, nameof(repository));
             }
 
             return efCoreRepository;
diff --git a/src/Volo.Abp.EntityFrameworkCore/Volo/Abp/Domain/Repositories/EntityFrameworkCore/EfCoreRepository.cs b/src/Volo.Abp.EntityFrameworkCore/Volo/Abp/Domain/Repositories/EntityFrameworkCore/EfCoreRepository.cs
index 9bd7245b7a..322096084d 100644
--- a/src/Volo.Abp.EntityFrameworkCore/Volo/Abp/Domain/Repositories/EntityFrameworkCore/EfCoreRepository.cs
+++ b/src/Volo.Abp.EntityFrameworkCore/Volo/Abp/Domain/Repositories/EntityFrameworkCore/EfCoreRepository.cs
@@ -95,12 +95,12 @@ namespace Volo.Abp.Domain.Repositories.EntityFrameworkCore
         }
     }
 
-    public class EfCoreRepository<TDbContext, TEntity, TPrimaryKey> : EfCoreRepository<TDbContext, TEntity>, 
-        IEfCoreRepository<TEntity, TPrimaryKey>,
-        ISupportsExplicitLoading<TEntity, TPrimaryKey>
+    public class EfCoreRepository<TDbContext, TEntity, TKey> : EfCoreRepository<TDbContext, TEntity>, 
+        IEfCoreRepository<TEntity, TKey>,
+        ISupportsExplicitLoading<TEntity, TKey>
 
         where TDbContext : IEfCoreDbContext
-        where TEntity : class, IEntity<TPrimaryKey>
+        where TEntity : class, IEntity<TKey>
     {
         public EfCoreRepository(IDbContextProvider<TDbContext> dbContextProvider) 
             : base(dbContextProvider)
@@ -108,7 +108,7 @@ namespace Volo.Abp.Domain.Repositories.EntityFrameworkCore
 
         }
 
-        public TEntity Get(TPrimaryKey id)
+        public TEntity Get(TKey id)
         {
             var entity = Find(id);
 
@@ -120,7 +120,7 @@ namespace Volo.Abp.Domain.Repositories.EntityFrameworkCore
             return entity;
         }
 
-        public virtual async Task<TEntity> GetAsync(TPrimaryKey id, CancellationToken cancellationToken = default)
+        public virtual async Task<TEntity> GetAsync(TKey id, CancellationToken cancellationToken = default)
         {
             var entity = await FindAsync(id, GetCancellationToken(cancellationToken));
 
@@ -132,17 +132,17 @@ namespace Volo.Abp.Domain.Repositories.EntityFrameworkCore
             return entity;
         }
 
-        public virtual TEntity Find(TPrimaryKey id)
+        public virtual TEntity Find(TKey id)
         {
             return DbSet.Find(id);
         }
 
-        public virtual Task<TEntity> FindAsync(TPrimaryKey id, CancellationToken cancellationToken = default)
+        public virtual Task<TEntity> FindAsync(TKey id, CancellationToken cancellationToken = default)
         {
             return DbSet.FindAsync(new object[] { id }, GetCancellationToken(cancellationToken));
         }
 
-        public virtual void Delete(TPrimaryKey id)
+        public virtual void Delete(TKey id)
         {
             var entity = Find(id);
             if (entity == null)
@@ -153,7 +153,7 @@ namespace Volo.Abp.Domain.Repositories.EntityFrameworkCore
             Delete(entity);
         }
 
-        public virtual Task DeleteAsync(TPrimaryKey id, CancellationToken cancellationToken = default)
+        public virtual Task DeleteAsync(TKey id, CancellationToken cancellationToken = default)
         {
             Delete(id);
             return Task.CompletedTask;
diff --git a/src/Volo.Abp.EntityFrameworkCore/Volo/Abp/Domain/Repositories/EntityFrameworkCore/IEfCoreRepository.cs b/src/Volo.Abp.EntityFrameworkCore/Volo/Abp/Domain/Repositories/EntityFrameworkCore/IEfCoreRepository.cs
index 8232f02fcd..b0354df4c9 100644
--- a/src/Volo.Abp.EntityFrameworkCore/Volo/Abp/Domain/Repositories/EntityFrameworkCore/IEfCoreRepository.cs
+++ b/src/Volo.Abp.EntityFrameworkCore/Volo/Abp/Domain/Repositories/EntityFrameworkCore/IEfCoreRepository.cs
@@ -11,8 +11,8 @@ namespace Volo.Abp.Domain.Repositories.EntityFrameworkCore
         DbSet<TEntity> DbSet { get; }
     }
 
-    public interface IEfCoreRepository<TEntity, TPrimaryKey> : IEfCoreRepository<TEntity>, IQueryableRepository<TEntity, TPrimaryKey>
-        where TEntity : class, IEntity<TPrimaryKey>
+    public interface IEfCoreRepository<TEntity, TKey> : IEfCoreRepository<TEntity>, IQueryableRepository<TEntity, TKey>
+        where TEntity : class, IEntity<TKey>
     {
 
     }
diff --git a/src/Volo.Abp.MemoryDb/Volo/Abp/Domain/Repositories/MemoryDb/IMemoryDatabase.cs b/src/Volo.Abp.MemoryDb/Volo/Abp/Domain/Repositories/MemoryDb/IMemoryDatabase.cs
index 7cbaf15e70..1e6cd6f54c 100644
--- a/src/Volo.Abp.MemoryDb/Volo/Abp/Domain/Repositories/MemoryDb/IMemoryDatabase.cs
+++ b/src/Volo.Abp.MemoryDb/Volo/Abp/Domain/Repositories/MemoryDb/IMemoryDatabase.cs
@@ -6,6 +6,6 @@ namespace Volo.Abp.Domain.Repositories.MemoryDb
     {
         List<TEntity> Collection<TEntity>();
 
-        TPrimaryKey GenerateNextId<TEntity, TPrimaryKey>();
+        TKey GenerateNextId<TEntity, TKey>();
     }
 }
\ No newline at end of file
diff --git a/src/Volo.Abp.MemoryDb/Volo/Abp/Domain/Repositories/MemoryDb/IMemoryDbRepository.cs b/src/Volo.Abp.MemoryDb/Volo/Abp/Domain/Repositories/MemoryDb/IMemoryDbRepository.cs
index 8d43180088..6b89208130 100644
--- a/src/Volo.Abp.MemoryDb/Volo/Abp/Domain/Repositories/MemoryDb/IMemoryDbRepository.cs
+++ b/src/Volo.Abp.MemoryDb/Volo/Abp/Domain/Repositories/MemoryDb/IMemoryDbRepository.cs
@@ -11,8 +11,8 @@ namespace Volo.Abp.Domain.Repositories.MemoryDb
         List<TEntity> Collection { get; }
     }
 
-    public interface IMemoryDbRepository<TEntity, TPrimaryKey> : IMemoryDbRepository<TEntity>, IQueryableRepository<TEntity, TPrimaryKey>
-        where TEntity : class, IEntity<TPrimaryKey>
+    public interface IMemoryDbRepository<TEntity, TKey> : IMemoryDbRepository<TEntity>, IQueryableRepository<TEntity, TKey>
+        where TEntity : class, IEntity<TKey>
     {
 
     }
diff --git a/src/Volo.Abp.MemoryDb/Volo/Abp/Domain/Repositories/MemoryDb/InMemoryIdGenerator.cs b/src/Volo.Abp.MemoryDb/Volo/Abp/Domain/Repositories/MemoryDb/InMemoryIdGenerator.cs
index 1741d2cc02..467fff5bc5 100644
--- a/src/Volo.Abp.MemoryDb/Volo/Abp/Domain/Repositories/MemoryDb/InMemoryIdGenerator.cs
+++ b/src/Volo.Abp.MemoryDb/Volo/Abp/Domain/Repositories/MemoryDb/InMemoryIdGenerator.cs
@@ -8,24 +8,24 @@ namespace Volo.Abp.Domain.Repositories.MemoryDb
         private int _lastInt;
         private long _lastLong;
 
-        public TPrimaryKey GenerateNext<TPrimaryKey>()
+        public TKey GenerateNext<TKey>()
         {
-            if (typeof(TPrimaryKey) == typeof(Guid))
+            if (typeof(TKey) == typeof(Guid))
             {
-                return (TPrimaryKey)(object)Guid.NewGuid();
+                return (TKey)(object)Guid.NewGuid();
             }
 
-            if (typeof(TPrimaryKey) == typeof(int))
+            if (typeof(TKey) == typeof(int))
             {
-                return (TPrimaryKey)(object)Interlocked.Increment(ref _lastInt);
+                return (TKey)(object)Interlocked.Increment(ref _lastInt);
             }
 
-            if (typeof(TPrimaryKey) == typeof(long))
+            if (typeof(TKey) == typeof(long))
             {
-                return (TPrimaryKey)(object)Interlocked.Increment(ref _lastLong);
+                return (TKey)(object)Interlocked.Increment(ref _lastLong);
             }
 
-            throw new AbpException("Not supported PrimaryKey type: " + typeof(TPrimaryKey).FullName);
+            throw new AbpException("Not supported PrimaryKey type: " + typeof(TKey).FullName);
         }
     }
 }
\ No newline at end of file
diff --git a/src/Volo.Abp.MemoryDb/Volo/Abp/Domain/Repositories/MemoryDb/MemoryDatabase.cs b/src/Volo.Abp.MemoryDb/Volo/Abp/Domain/Repositories/MemoryDb/MemoryDatabase.cs
index 332138eae2..212c151087 100644
--- a/src/Volo.Abp.MemoryDb/Volo/Abp/Domain/Repositories/MemoryDb/MemoryDatabase.cs
+++ b/src/Volo.Abp.MemoryDb/Volo/Abp/Domain/Repositories/MemoryDb/MemoryDatabase.cs
@@ -21,11 +21,11 @@ namespace Volo.Abp.Domain.Repositories.MemoryDb
             return _sets.GetOrAdd(typeof(TEntity), _ => new List<TEntity>()) as List<TEntity>;
         }
 
-        public TPrimaryKey GenerateNextId<TEntity, TPrimaryKey>()
+        public TKey GenerateNextId<TEntity, TKey>()
         {
             return _idGenerators
                 .GetOrAdd(typeof(TEntity), () => new InMemoryIdGenerator())
-                .GenerateNext<TPrimaryKey>();
+                .GenerateNext<TKey>();
         }
     }
 }
\ No newline at end of file
diff --git a/src/Volo.Abp.MemoryDb/Volo/Abp/Domain/Repositories/MemoryDb/MemoryDbRepository.cs b/src/Volo.Abp.MemoryDb/Volo/Abp/Domain/Repositories/MemoryDb/MemoryDbRepository.cs
index acd37028a4..72e84d126f 100644
--- a/src/Volo.Abp.MemoryDb/Volo/Abp/Domain/Repositories/MemoryDb/MemoryDbRepository.cs
+++ b/src/Volo.Abp.MemoryDb/Volo/Abp/Domain/Repositories/MemoryDb/MemoryDbRepository.cs
@@ -45,9 +45,9 @@ namespace Volo.Abp.Domain.Repositories.MemoryDb
         }
     }
 
-    public class MemoryDbRepository<TMemoryDbContext, TEntity, TPrimaryKey> : MemoryDbRepository<TMemoryDbContext, TEntity>, IMemoryDbRepository<TEntity, TPrimaryKey> 
+    public class MemoryDbRepository<TMemoryDbContext, TEntity, TKey> : MemoryDbRepository<TMemoryDbContext, TEntity>, IMemoryDbRepository<TEntity, TKey> 
         where TMemoryDbContext : MemoryDbContext
-        where TEntity : class, IEntity<TPrimaryKey>
+        where TEntity : class, IEntity<TKey>
     {
         public MemoryDbRepository(IMemoryDatabaseProvider<TMemoryDbContext> databaseProvider)
             : base(databaseProvider)
@@ -62,21 +62,21 @@ namespace Volo.Abp.Domain.Repositories.MemoryDb
 
         private void SetIdIfNeeded(TEntity entity)
         {
-            if (typeof(TPrimaryKey) == typeof(int) || typeof(TPrimaryKey) == typeof(long) || typeof(TPrimaryKey) == typeof(Guid))
+            if (typeof(TKey) == typeof(int) || typeof(TKey) == typeof(long) || typeof(TKey) == typeof(Guid))
             {
                 if (EntityHelper.IsTransient(entity))
                 {
-                    entity.Id = Database.GenerateNextId<TEntity, TPrimaryKey>();
+                    entity.Id = Database.GenerateNextId<TEntity, TKey>();
                 }
             }
         }
 
-        public virtual TEntity Find(TPrimaryKey id)
+        public virtual TEntity Find(TKey id)
         {
-            return GetQueryable().FirstOrDefault(EntityHelper.CreateEqualityExpressionForId<TEntity, TPrimaryKey>(id));
+            return GetQueryable().FirstOrDefault(EntityHelper.CreateEqualityExpressionForId<TEntity, TKey>(id));
         }
 
-        public virtual TEntity Get(TPrimaryKey id)
+        public virtual TEntity Get(TKey id)
         {
             var entity = Find(id);
 
@@ -88,17 +88,17 @@ namespace Volo.Abp.Domain.Repositories.MemoryDb
             return entity;
         }
 
-        public virtual Task<TEntity> GetAsync(TPrimaryKey id, CancellationToken cancellationToken = default)
+        public virtual Task<TEntity> GetAsync(TKey id, CancellationToken cancellationToken = default)
         {
             return Task.FromResult(Get(id));
         }
 
-        public virtual Task<TEntity> FindAsync(TPrimaryKey id, CancellationToken cancellationToken = default)
+        public virtual Task<TEntity> FindAsync(TKey id, CancellationToken cancellationToken = default)
         {
             return Task.FromResult(Find(id));
         }
 
-        public virtual void Delete(TPrimaryKey id)
+        public virtual void Delete(TKey id)
         {
             var entity = Find(id);
             if (entity == null)
@@ -109,7 +109,7 @@ namespace Volo.Abp.Domain.Repositories.MemoryDb
             Delete(entity);
         }
 
-        public virtual Task DeleteAsync(TPrimaryKey id, CancellationToken cancellationToken = default)
+        public virtual Task DeleteAsync(TKey id, CancellationToken cancellationToken = default)
         {
             Delete(id);
             return Task.CompletedTask;
diff --git a/src/Volo.Abp.MemoryDb/Volo/Abp/Domain/Repositories/MemoryDbCoreRepositoryExtensions.cs b/src/Volo.Abp.MemoryDb/Volo/Abp/Domain/Repositories/MemoryDbCoreRepositoryExtensions.cs
index 71192d03ed..4071646c7d 100644
--- a/src/Volo.Abp.MemoryDb/Volo/Abp/Domain/Repositories/MemoryDbCoreRepositoryExtensions.cs
+++ b/src/Volo.Abp.MemoryDb/Volo/Abp/Domain/Repositories/MemoryDbCoreRepositoryExtensions.cs
@@ -7,25 +7,25 @@ namespace Volo.Abp.Domain.Repositories
 {
     public static class MemoryDbCoreRepositoryExtensions
     {
-        public static IMemoryDatabase GetDatabase<TEntity, TPrimaryKey>(this IRepository<TEntity, TPrimaryKey> repository)
-            where TEntity : class, IEntity<TPrimaryKey>
+        public static IMemoryDatabase GetDatabase<TEntity, TKey>(this IRepository<TEntity, TKey> repository)
+            where TEntity : class, IEntity<TKey>
         {
             return repository.ToMemoryDbRepository().Database;
         }
 
-        public static List<TEntity> GetCollection<TEntity, TPrimaryKey>(this IRepository<TEntity, TPrimaryKey> repository)
-            where TEntity : class, IEntity<TPrimaryKey>
+        public static List<TEntity> GetCollection<TEntity, TKey>(this IRepository<TEntity, TKey> repository)
+            where TEntity : class, IEntity<TKey>
         {
             return repository.ToMemoryDbRepository().Collection;
         }
 
-        public static IMemoryDbRepository<TEntity, TPrimaryKey> ToMemoryDbRepository<TEntity, TPrimaryKey>(this IRepository<TEntity, TPrimaryKey> repository)
-            where TEntity : class, IEntity<TPrimaryKey>
+        public static IMemoryDbRepository<TEntity, TKey> ToMemoryDbRepository<TEntity, TKey>(this IRepository<TEntity, TKey> repository)
+            where TEntity : class, IEntity<TKey>
         {
-            var memoryDbRepository = repository as IMemoryDbRepository<TEntity, TPrimaryKey>;
+            var memoryDbRepository = repository as IMemoryDbRepository<TEntity, TKey>;
             if (memoryDbRepository == null)
             {
-                throw new ArgumentException("Given repository does not implement " + typeof(IMemoryDbRepository<TEntity, TPrimaryKey>).AssemblyQualifiedName, nameof(repository));
+                throw new ArgumentException("Given repository does not implement " + typeof(IMemoryDbRepository<TEntity, TKey>).AssemblyQualifiedName, nameof(repository));
             }
 
             return memoryDbRepository;
diff --git a/src/Volo.Abp.MongoDB/Volo/Abp/Domain/Repositories/MongoDB/IMongoDbRepository.cs b/src/Volo.Abp.MongoDB/Volo/Abp/Domain/Repositories/MongoDB/IMongoDbRepository.cs
index c20c5dca1e..c8f5eb0265 100644
--- a/src/Volo.Abp.MongoDB/Volo/Abp/Domain/Repositories/MongoDB/IMongoDbRepository.cs
+++ b/src/Volo.Abp.MongoDB/Volo/Abp/Domain/Repositories/MongoDB/IMongoDbRepository.cs
@@ -13,8 +13,8 @@ namespace Volo.Abp.Domain.Repositories.MongoDB
         string CollectionName { get; }
     }
 
-    public interface IMongoDbRepository<TEntity, TPrimaryKey> : IMongoDbRepository<TEntity>, IQueryableRepository<TEntity, TPrimaryKey>
-        where TEntity : class, IEntity<TPrimaryKey>
+    public interface IMongoDbRepository<TEntity, TKey> : IMongoDbRepository<TEntity>, IQueryableRepository<TEntity, TKey>
+        where TEntity : class, IEntity<TKey>
     {
 
     }
diff --git a/src/Volo.Abp.MongoDB/Volo/Abp/Domain/Repositories/MongoDB/MongoDbRepository.cs b/src/Volo.Abp.MongoDB/Volo/Abp/Domain/Repositories/MongoDB/MongoDbRepository.cs
index 3141da949e..348ed9e957 100644
--- a/src/Volo.Abp.MongoDB/Volo/Abp/Domain/Repositories/MongoDB/MongoDbRepository.cs
+++ b/src/Volo.Abp.MongoDB/Volo/Abp/Domain/Repositories/MongoDB/MongoDbRepository.cs
@@ -81,9 +81,9 @@ namespace Volo.Abp.Domain.Repositories.MongoDB
         }
     }
 
-    public class MongoDbRepository<TMongoDbContext, TEntity, TPrimaryKey> : MongoDbRepository<TMongoDbContext, TEntity>, IMongoDbRepository<TEntity, TPrimaryKey>
+    public class MongoDbRepository<TMongoDbContext, TEntity, TKey> : MongoDbRepository<TMongoDbContext, TEntity>, IMongoDbRepository<TEntity, TKey>
         where TMongoDbContext : AbpMongoDbContext
-        where TEntity : class, IEntity<TPrimaryKey>
+        where TEntity : class, IEntity<TKey>
     {
         public MongoDbRepository(IMongoDatabaseProvider<TMongoDbContext> databaseProvider)
             : base(databaseProvider)
@@ -91,7 +91,7 @@ namespace Volo.Abp.Domain.Repositories.MongoDB
 
         }
 
-        public virtual TEntity Get(TPrimaryKey id)
+        public virtual TEntity Get(TKey id)
         {
             var entity = Find(id);
 
@@ -103,7 +103,7 @@ namespace Volo.Abp.Domain.Repositories.MongoDB
             return entity;
         }
 
-        public virtual async Task<TEntity> GetAsync(TPrimaryKey id, CancellationToken cancellationToken = default)
+        public virtual async Task<TEntity> GetAsync(TKey id, CancellationToken cancellationToken = default)
         {
             var entity = await FindAsync(id, cancellationToken);
 
@@ -115,22 +115,22 @@ namespace Volo.Abp.Domain.Repositories.MongoDB
             return entity;
         }
 
-        public virtual void Delete(TPrimaryKey id)
+        public virtual void Delete(TKey id)
         {
             Collection.DeleteOne(CreateEntityFilter(id));
         }
 
-        public virtual Task DeleteAsync(TPrimaryKey id, CancellationToken cancellationToken = default)
+        public virtual Task DeleteAsync(TKey id, CancellationToken cancellationToken = default)
         {
             return Collection.DeleteOneAsync(CreateEntityFilter(id), cancellationToken);
         }
 
-        public virtual async Task<TEntity> FindAsync(TPrimaryKey id, CancellationToken cancellationToken = default)
+        public virtual async Task<TEntity> FindAsync(TKey id, CancellationToken cancellationToken = default)
         {
             return await Collection.Find(CreateEntityFilter(id)).FirstOrDefaultAsync(cancellationToken);
         }
 
-        public virtual TEntity Find(TPrimaryKey id)
+        public virtual TEntity Find(TKey id)
         {
             return Collection.Find(CreateEntityFilter(id)).FirstOrDefault();
         }
@@ -140,7 +140,7 @@ namespace Volo.Abp.Domain.Repositories.MongoDB
             return Builders<TEntity>.Filter.Eq(e => e.Id, entity.Id);
         }
 
-        private static FilterDefinition<TEntity> CreateEntityFilter(TPrimaryKey id)
+        private static FilterDefinition<TEntity> CreateEntityFilter(TKey id)
         {
             return Builders<TEntity>.Filter.Eq(e => e.Id, id);
         }
diff --git a/src/Volo.Abp.MongoDB/Volo/Abp/Domain/Repositories/MongoDbCoreRepositoryExtensions.cs b/src/Volo.Abp.MongoDB/Volo/Abp/Domain/Repositories/MongoDbCoreRepositoryExtensions.cs
index b553637002..dba22e8e1b 100644
--- a/src/Volo.Abp.MongoDB/Volo/Abp/Domain/Repositories/MongoDbCoreRepositoryExtensions.cs
+++ b/src/Volo.Abp.MongoDB/Volo/Abp/Domain/Repositories/MongoDbCoreRepositoryExtensions.cs
@@ -7,31 +7,31 @@ namespace Volo.Abp.Domain.Repositories
 {
     public static class MongoDbCoreRepositoryExtensions
     {
-        public static IMongoDatabase GetDatabase<TEntity, TPrimaryKey>(this IRepository<TEntity, TPrimaryKey> repository)
-            where TEntity : class, IEntity<TPrimaryKey>
+        public static IMongoDatabase GetDatabase<TEntity, TKey>(this IRepository<TEntity, TKey> repository)
+            where TEntity : class, IEntity<TKey>
         {
             return repository.ToMongoDbRepository().Database;
         }
 
-        public static IMongoCollection<TEntity> GetCollection<TEntity, TPrimaryKey>(this IRepository<TEntity, TPrimaryKey> repository)
-            where TEntity : class, IEntity<TPrimaryKey>
+        public static IMongoCollection<TEntity> GetCollection<TEntity, TKey>(this IRepository<TEntity, TKey> repository)
+            where TEntity : class, IEntity<TKey>
         {
             return repository.ToMongoDbRepository().Collection;
         }
 
-        public static string GetCollectionName<TEntity, TPrimaryKey>(this IRepository<TEntity, TPrimaryKey> repository)
-            where TEntity : class, IEntity<TPrimaryKey>
+        public static string GetCollectionName<TEntity, TKey>(this IRepository<TEntity, TKey> repository)
+            where TEntity : class, IEntity<TKey>
         {
             return repository.ToMongoDbRepository().CollectionName;
         }
 
-        public static IMongoDbRepository<TEntity, TPrimaryKey> ToMongoDbRepository<TEntity, TPrimaryKey>(this IRepository<TEntity, TPrimaryKey> repository)
-            where TEntity : class, IEntity<TPrimaryKey>
+        public static IMongoDbRepository<TEntity, TKey> ToMongoDbRepository<TEntity, TKey>(this IRepository<TEntity, TKey> repository)
+            where TEntity : class, IEntity<TKey>
         {
-            var mongoDbRepository = repository as IMongoDbRepository<TEntity, TPrimaryKey>;
+            var mongoDbRepository = repository as IMongoDbRepository<TEntity, TKey>;
             if (mongoDbRepository == null)
             {
-                throw new ArgumentException("Given repository does not implement " + typeof(IMongoDbRepository<TEntity, TPrimaryKey>).AssemblyQualifiedName, nameof(repository));
+                throw new ArgumentException("Given repository does not implement " + typeof(IMongoDbRepository<TEntity, TKey>).AssemblyQualifiedName, nameof(repository));
             }
 
             return mongoDbRepository;
diff --git a/test/Volo.Abp.Ddd.Tests/Volo/Abp/Domain/Repositories/RepositoryRegistration_Tests.cs b/test/Volo.Abp.Ddd.Tests/Volo/Abp/Domain/Repositories/RepositoryRegistration_Tests.cs
index 372f3fb6b9..5f082eb52a 100644
--- a/test/Volo.Abp.Ddd.Tests/Volo/Abp/Domain/Repositories/RepositoryRegistration_Tests.cs
+++ b/test/Volo.Abp.Ddd.Tests/Volo/Abp/Domain/Repositories/RepositoryRegistration_Tests.cs
@@ -169,35 +169,35 @@ namespace Volo.Abp.Domain.Repositories
             }
         }
 
-        public class MyTestDefaultRepository<TEntity, TPrimaryKey> : MyTestDefaultRepository<TEntity>, IRepository<TEntity, TPrimaryKey>
-            where TEntity : class, IEntity<TPrimaryKey>
+        public class MyTestDefaultRepository<TEntity, TKey> : MyTestDefaultRepository<TEntity>, IRepository<TEntity, TKey>
+            where TEntity : class, IEntity<TKey>
         {
-            public TEntity Get(TPrimaryKey id)
+            public TEntity Get(TKey id)
             {
                 throw new NotImplementedException();
             }
 
-            public Task<TEntity> GetAsync(TPrimaryKey id, CancellationToken cancellationToken = default)
+            public Task<TEntity> GetAsync(TKey id, CancellationToken cancellationToken = default)
             {
                 throw new NotImplementedException();
             }
 
-            public TEntity Find(TPrimaryKey id)
+            public TEntity Find(TKey id)
             {
                 throw new NotImplementedException();
             }
 
-            public Task<TEntity> FindAsync(TPrimaryKey id, CancellationToken cancellationToken = default)
+            public Task<TEntity> FindAsync(TKey id, CancellationToken cancellationToken = default)
             {
                 throw new NotImplementedException();
             }
 
-            public void Delete(TPrimaryKey id)
+            public void Delete(TKey id)
             {
                 throw new NotImplementedException();
             }
 
-            public Task DeleteAsync(TPrimaryKey id, CancellationToken cancellationToken = default)
+            public Task DeleteAsync(TKey id, CancellationToken cancellationToken = default)
             {
                 throw new NotImplementedException();
             }
@@ -214,8 +214,8 @@ namespace Volo.Abp.Domain.Repositories
 
         }
 
-        public class MyTestCustomBaseRepository<TEntity, TPrimaryKey> : MyTestDefaultRepository<TEntity, TPrimaryKey>
-            where TEntity : class, IEntity<TPrimaryKey>
+        public class MyTestCustomBaseRepository<TEntity, TKey> : MyTestDefaultRepository<TEntity, TKey>
+            where TEntity : class, IEntity<TKey>
         {
 
         }
diff --git a/test/Volo.Abp.TestApp/Volo/Abp/TestApp/Domain/Phone.cs b/test/Volo.Abp.TestApp/Volo/Abp/TestApp/Domain/Phone.cs
index 45f31c705b..142e97463e 100644
--- a/test/Volo.Abp.TestApp/Volo/Abp/TestApp/Domain/Phone.cs
+++ b/test/Volo.Abp.TestApp/Volo/Abp/TestApp/Domain/Phone.cs
@@ -1,5 +1,7 @@
 using System;
+using System.Collections.Generic;
 using System.ComponentModel.DataAnnotations.Schema;
+using System.Linq;
 using Volo.Abp.Domain.Entities;
 
 namespace Volo.Abp.TestApp.Domain
@@ -25,4 +27,74 @@ namespace Volo.Abp.TestApp.Domain
             Type = type;
         }
     }
+
+    public class Order : AggregateRoot<Guid>
+    {
+        public virtual string ReferenceNo { get; protected set; }
+
+        public virtual float TotalItemCount { get; protected set; }
+
+        public virtual DateTime CreationTime { get; protected set; }
+
+        public virtual List<OrderLine> OrderLines { get; protected set; }
+
+        protected Order()
+        {
+            
+        }
+
+        public Order(Guid id, string referenceNo)
+        {
+            Id = id;
+            ReferenceNo = referenceNo;
+            OrderLines = new List<OrderLine>();
+        }
+
+        public void AddProduct(Guid productId, int count)
+        {
+            if (count <= 0)
+            {
+                throw new ArgumentException("You can not add zero or negative count of products!", nameof(count));
+            }
+
+            var existingLine = OrderLines.FirstOrDefault(ol => ol.ProductId == productId);
+
+            if (existingLine == null)
+            {
+                OrderLines.Add(new OrderLine(this.Id, productId, count));
+            }
+            else
+            {
+                existingLine.ChangeCount(existingLine.Count + count);
+            }
+
+            TotalItemCount += count;
+        }
+    }
+
+    public class OrderLine : Entity
+    {
+        public virtual Guid OrderId { get; protected set; }
+
+        public virtual Guid ProductId { get; protected set; }
+
+        public virtual int Count { get; protected set; }
+
+        protected OrderLine()
+        {
+
+        }
+
+        public OrderLine(Guid orderId, Guid productId, int count)
+        {
+            OrderId = orderId;
+            ProductId = productId;
+            Count = count;
+        }
+
+        internal void ChangeCount(int newCount)
+        {
+            Count = newCount;
+        }
+    }
 }
\ No newline at end of file