diff --git a/modules/cms-kit/src/Volo.CmsKit.Admin.Application.Contracts/Volo/CmsKit/Admin/Tags/TagCreateDto.cs b/modules/cms-kit/src/Volo.CmsKit.Admin.Application.Contracts/Volo/CmsKit/Admin/Tags/TagCreateDto.cs
index 3eb75bec07..6dd90d1362 100644
--- a/modules/cms-kit/src/Volo.CmsKit.Admin.Application.Contracts/Volo/CmsKit/Admin/Tags/TagCreateDto.cs
+++ b/modules/cms-kit/src/Volo.CmsKit.Admin.Application.Contracts/Volo/CmsKit/Admin/Tags/TagCreateDto.cs
@@ -1,12 +1,17 @@
 using System.ComponentModel.DataAnnotations;
+using Volo.Abp.Validation;
+using Volo.CmsKit.Tags;
 
 namespace Volo.CmsKit.Admin.Tags
 {
     public class TagCreateDto
     {
         [Required]
+        [DynamicMaxLength(typeof(TagConsts), nameof(TagConsts.MaxEntityTypeLength))]
         public string EntityType { get; set; }
+
         [Required]
+        [DynamicMaxLength(typeof(TagConsts), nameof(TagConsts.MaxNameLength))]
         public string Name { get; set; }
     }
 }
diff --git a/modules/cms-kit/src/Volo.CmsKit.Admin.Application.Contracts/Volo/CmsKit/Admin/Tags/TagUpdateDto.cs b/modules/cms-kit/src/Volo.CmsKit.Admin.Application.Contracts/Volo/CmsKit/Admin/Tags/TagUpdateDto.cs
index 4df242a997..c4298b7730 100644
--- a/modules/cms-kit/src/Volo.CmsKit.Admin.Application.Contracts/Volo/CmsKit/Admin/Tags/TagUpdateDto.cs
+++ b/modules/cms-kit/src/Volo.CmsKit.Admin.Application.Contracts/Volo/CmsKit/Admin/Tags/TagUpdateDto.cs
@@ -1,10 +1,13 @@
 using System.ComponentModel.DataAnnotations;
+using Volo.Abp.Validation;
+using Volo.CmsKit.Tags;
 
 namespace Volo.CmsKit.Admin.Tags
 {
     public class TagUpdateDto
     {
         [Required]
+        [DynamicMaxLength(typeof(TagConsts), nameof(TagConsts.MaxNameLength))]
         public string Name { get; set; }
     }
 }
diff --git a/modules/cms-kit/src/Volo.CmsKit.Domain.Shared/Volo/CmsKit/CmsKitErrorCodes.cs b/modules/cms-kit/src/Volo.CmsKit.Domain.Shared/Volo/CmsKit/CmsKitErrorCodes.cs
index 336d163cfe..76ba39c3f2 100644
--- a/modules/cms-kit/src/Volo.CmsKit.Domain.Shared/Volo/CmsKit/CmsKitErrorCodes.cs
+++ b/modules/cms-kit/src/Volo.CmsKit.Domain.Shared/Volo/CmsKit/CmsKitErrorCodes.cs
@@ -2,6 +2,6 @@
 {
     public static class CmsKitErrorCodes
     {
-        //Add your business exception error codes here...
+        public const string TagAlreadyExist = "CmsKit:0001";
     }
 }
diff --git a/modules/cms-kit/src/Volo.CmsKit.Domain/Volo/CmsKit/Tags/TagAlreadyExistException.cs b/modules/cms-kit/src/Volo.CmsKit.Domain/Volo/CmsKit/Tags/TagAlreadyExistException.cs
new file mode 100644
index 0000000000..6cae0dde92
--- /dev/null
+++ b/modules/cms-kit/src/Volo.CmsKit.Domain/Volo/CmsKit/Tags/TagAlreadyExistException.cs
@@ -0,0 +1,17 @@
+using JetBrains.Annotations;
+using System;
+using Volo.Abp;
+
+namespace Volo.CmsKit.Tags
+{
+    [Serializable]
+    public class TagAlreadyExistException : BusinessException
+    {
+        public TagAlreadyExistException([NotNull] string entityType, [NotNull] string name)
+        {
+            Code = CmsKitErrorCodes.TagAlreadyExist;
+            WithData(nameof(Tag.EntityType), entityType);
+            WithData(nameof(Tag.Name), name);
+        }
+    }
+}
diff --git a/modules/cms-kit/src/Volo.CmsKit.Domain/Volo/CmsKit/Tags/TagManager.cs b/modules/cms-kit/src/Volo.CmsKit.Domain/Volo/CmsKit/Tags/TagManager.cs
index e1e9366a99..042b4e27a9 100644
--- a/modules/cms-kit/src/Volo.CmsKit.Domain/Volo/CmsKit/Tags/TagManager.cs
+++ b/modules/cms-kit/src/Volo.CmsKit.Domain/Volo/CmsKit/Tags/TagManager.cs
@@ -41,7 +41,7 @@ namespace Volo.CmsKit.Tags
         {
             if (await _tagRepository.AnyAsync(entityType, name, tenantId, cancellationToken))
             {
-                throw new BusinessException(message: "Tag already exist!"); // Already Exist
+                throw new TagAlreadyExistException(entityType, name);
             }
 
             return await _tagRepository.InsertAsync(
@@ -63,7 +63,7 @@ namespace Volo.CmsKit.Tags
             if (name != entity.Name &&
                 await _tagRepository.AnyAsync(entity.EntityType, name, entity.TenantId, cancellationToken))
             {
-                throw new BusinessException(message: "Tag already exist!"); // Already Exist
+                throw new TagAlreadyExistException(entity.EntityType, name);
             }
 
             entity.SetName(name);
diff --git a/modules/cms-kit/test/Volo.CmsKit.Application.Tests/Tags/TagAdminAppService_Tests.cs b/modules/cms-kit/test/Volo.CmsKit.Application.Tests/Tags/TagAdminAppService_Tests.cs
new file mode 100644
index 0000000000..4ad0d43468
--- /dev/null
+++ b/modules/cms-kit/test/Volo.CmsKit.Application.Tests/Tags/TagAdminAppService_Tests.cs
@@ -0,0 +1,52 @@
+using Microsoft.Extensions.DependencyInjection;
+using NSubstitute;
+using Shouldly;
+using System;
+using System.Threading.Tasks;
+using Volo.Abp.Users;
+using Volo.CmsKit.Admin.Tags;
+using Xunit;
+
+namespace Volo.CmsKit.Tags
+{
+    public class TagAdminAppService_Tests : CmsKitApplicationTestBase
+    {
+        private readonly ITagAdminAppService _tagAdminAppService;
+        private ICurrentUser _currentUser;
+        private readonly CmsKitTestData _cmsKitTestData;
+
+        public TagAdminAppService_Tests()
+        {
+            _tagAdminAppService = GetRequiredService<ITagAdminAppService>();
+            _cmsKitTestData = GetRequiredService<CmsKitTestData>();
+        }
+
+        protected override void AfterAddApplication(IServiceCollection services)
+        {
+            _currentUser = Substitute.For<ICurrentUser>();
+            services.AddSingleton(_currentUser);
+        }
+
+        [Fact]
+        public async Task ShouldCreateProperly()
+        {
+            var list = await _tagAdminAppService.CreateAsync(new TagCreateDto
+            {
+                EntityType = "any_new_type",
+                Name = "1",
+            });
+
+            list.Id.ShouldNotBe(Guid.Empty);
+        }
+
+        [Fact]
+        public async Task ShouldThrowException_WhenTagAlreadyExist()
+        {
+            await Should.ThrowAsync<TagAlreadyExistException>(async () => await _tagAdminAppService.CreateAsync(new TagCreateDto
+            {
+                EntityType = _cmsKitTestData.Content_1_EntityType,
+                Name = _cmsKitTestData.Content_1_Tags[0],
+            }));
+        }
+    }
+}
diff --git a/modules/cms-kit/test/Volo.CmsKit.Application.Tests/Tags/TagAppService_Tests.cs b/modules/cms-kit/test/Volo.CmsKit.Application.Tests/Tags/TagPublicAppService_Tests.cs
similarity index 95%
rename from modules/cms-kit/test/Volo.CmsKit.Application.Tests/Tags/TagAppService_Tests.cs
rename to modules/cms-kit/test/Volo.CmsKit.Application.Tests/Tags/TagPublicAppService_Tests.cs
index 35b46b5a04..6ad1136167 100644
--- a/modules/cms-kit/test/Volo.CmsKit.Application.Tests/Tags/TagAppService_Tests.cs
+++ b/modules/cms-kit/test/Volo.CmsKit.Application.Tests/Tags/TagPublicAppService_Tests.cs
@@ -10,13 +10,13 @@ using Xunit;
 
 namespace Volo.CmsKit.Tags
 {
-    public class TagAppService_Tests : CmsKitApplicationTestBase
+    public class TagPublicAppService_Tests : CmsKitApplicationTestBase
     {
         private readonly ITagAppService _tagAppService;
         private ICurrentUser _currentUser;
         private readonly CmsKitTestData _cmsKitTestData;
 
-        public TagAppService_Tests()
+        public TagPublicAppService_Tests()
         {
             _tagAppService = GetRequiredService<ITagAppService>();
             _cmsKitTestData = GetRequiredService<CmsKitTestData>();