diff --git a/framework/src/Volo.Abp.Dapper/Volo.Abp.Dapper.csproj b/framework/src/Volo.Abp.Dapper/Volo.Abp.Dapper.csproj
index e4236d697c..e42eca0d2b 100644
--- a/framework/src/Volo.Abp.Dapper/Volo.Abp.Dapper.csproj
+++ b/framework/src/Volo.Abp.Dapper/Volo.Abp.Dapper.csproj
@@ -5,6 +5,8 @@
 
   <PropertyGroup>
     <TargetFramework>net7.0</TargetFramework>
+    <Nullable>enable</Nullable>
+    <WarningsAsErrors>Nullable</WarningsAsErrors>
     <AssemblyName>Volo.Abp.Dapper</AssemblyName>
     <PackageId>Volo.Abp.Dapper</PackageId>
     <AssetTargetFallback>$(AssetTargetFallback);portable-net45+win8+wp8+wpa81;</AssetTargetFallback>
diff --git a/framework/src/Volo.Abp.Dapper/Volo/Abp/Domain/Repositories/Dapper/DapperRepository.cs b/framework/src/Volo.Abp.Dapper/Volo/Abp/Domain/Repositories/Dapper/DapperRepository.cs
index b9f061b9aa..fda89ab61d 100644
--- a/framework/src/Volo.Abp.Dapper/Volo/Abp/Domain/Repositories/Dapper/DapperRepository.cs
+++ b/framework/src/Volo.Abp.Dapper/Volo/Abp/Domain/Repositories/Dapper/DapperRepository.cs
@@ -16,7 +16,7 @@ namespace Volo.Abp.Domain.Repositories.Dapper;
 public class DapperRepository<TDbContext> : IDapperRepository, IUnitOfWorkEnabled
     where TDbContext : IEfCoreDbContext
 {
-    public IAbpLazyServiceProvider LazyServiceProvider { get; set; }
+    public IAbpLazyServiceProvider LazyServiceProvider { get; set; } = default!;
 
     public IDataFilter DataFilter => LazyServiceProvider.LazyGetRequiredService<IDataFilter>();
 
@@ -39,9 +39,9 @@ public class DapperRepository<TDbContext> : IDapperRepository, IUnitOfWorkEnable
     public virtual async Task<IDbConnection> GetDbConnectionAsync() => (await _dbContextProvider.GetDbContextAsync()).Database.GetDbConnection();
 
     [Obsolete("Use GetDbTransactionAsync method.")]
-    public IDbTransaction DbTransaction => _dbContextProvider.GetDbContext().Database.CurrentTransaction?.GetDbTransaction();
+    public IDbTransaction? DbTransaction => _dbContextProvider.GetDbContext().Database.CurrentTransaction?.GetDbTransaction();
 
-    public virtual async Task<IDbTransaction> GetDbTransactionAsync() => (await _dbContextProvider.GetDbContextAsync()).Database.CurrentTransaction?.GetDbTransaction();
+    public virtual async Task<IDbTransaction?> GetDbTransactionAsync() => (await _dbContextProvider.GetDbContextAsync()).Database.CurrentTransaction?.GetDbTransaction();
 
     protected virtual CancellationToken GetCancellationToken(CancellationToken preferredValue = default)
     {
diff --git a/framework/src/Volo.Abp.Dapper/Volo/Abp/Domain/Repositories/Dapper/IDapperRepository.cs b/framework/src/Volo.Abp.Dapper/Volo/Abp/Domain/Repositories/Dapper/IDapperRepository.cs
index e5e8fa4c54..5a22e65e00 100644
--- a/framework/src/Volo.Abp.Dapper/Volo/Abp/Domain/Repositories/Dapper/IDapperRepository.cs
+++ b/framework/src/Volo.Abp.Dapper/Volo/Abp/Domain/Repositories/Dapper/IDapperRepository.cs
@@ -12,7 +12,7 @@ public interface IDapperRepository
     Task<IDbConnection> GetDbConnectionAsync();
 
     [Obsolete("Use GetDbTransactionAsync method.")]
-    IDbTransaction DbTransaction { get; }
+    IDbTransaction? DbTransaction { get; }
 
-    Task<IDbTransaction> GetDbTransactionAsync();
+    Task<IDbTransaction?> GetDbTransactionAsync();
 }