diff --git a/modules/identity/src/Volo.Abp.Identity.EntityFrameworkCore/Volo/Abp/Identity/EntityFrameworkCore/EfCoreIdentityUserRepository.cs b/modules/identity/src/Volo.Abp.Identity.EntityFrameworkCore/Volo/Abp/Identity/EntityFrameworkCore/EfCoreIdentityUserRepository.cs
index 81488b1f30..c52902bfed 100644
--- a/modules/identity/src/Volo.Abp.Identity.EntityFrameworkCore/Volo/Abp/Identity/EntityFrameworkCore/EfCoreIdentityUserRepository.cs
+++ b/modules/identity/src/Volo.Abp.Identity.EntityFrameworkCore/Volo/Abp/Identity/EntityFrameworkCore/EfCoreIdentityUserRepository.cs
@@ -174,13 +174,14 @@ public class EfCoreIdentityUserRepository : EfCoreRepository<IIdentityDbContext,
         DateTime? minModifitionTime = null,
         CancellationToken cancellationToken = default)
     {
+        var upperFilter = filter?.ToUpperInvariant();
         return await (await GetDbSetAsync())
             .IncludeDetails(includeDetails)
             .WhereIf(
                 !filter.IsNullOrWhiteSpace(),
                 u =>
-                    u.UserName.Contains(filter) ||
-                    u.Email.Contains(filter) ||
+                    u.NormalizedUserName.Contains(upperFilter) ||
+                    u.NormalizedEmail.Contains(upperFilter) ||
                     (u.Name != null && u.Name.Contains(filter)) ||
                     (u.Surname != null && u.Surname.Contains(filter)) ||
                     (u.PhoneNumber != null && u.PhoneNumber.Contains(filter))
@@ -255,12 +256,13 @@ public class EfCoreIdentityUserRepository : EfCoreRepository<IIdentityDbContext,
         DateTime? minModifitionTime = null,
         CancellationToken cancellationToken = default)
     {
+        var upperFilter = filter?.ToUpperInvariant();
         return await (await GetDbSetAsync())
             .WhereIf(
                 !filter.IsNullOrWhiteSpace(),
                 u =>
-                    u.UserName.Contains(filter) ||
-                    u.Email.Contains(filter) ||
+                    u.NormalizedUserName.Contains(upperFilter) ||
+                    u.NormalizedEmail.Contains(upperFilter) ||
                     (u.Name != null && u.Name.Contains(filter)) ||
                     (u.Surname != null && u.Surname.Contains(filter)) ||
                     (u.PhoneNumber != null && u.PhoneNumber.Contains(filter))
diff --git a/modules/identity/src/Volo.Abp.Identity.MongoDB/Volo/Abp/Identity/MongoDB/MongoIdentityUserRepository.cs b/modules/identity/src/Volo.Abp.Identity.MongoDB/Volo/Abp/Identity/MongoDB/MongoIdentityUserRepository.cs
index f5589d5dfa..51960edbba 100644
--- a/modules/identity/src/Volo.Abp.Identity.MongoDB/Volo/Abp/Identity/MongoDB/MongoIdentityUserRepository.cs
+++ b/modules/identity/src/Volo.Abp.Identity.MongoDB/Volo/Abp/Identity/MongoDB/MongoIdentityUserRepository.cs
@@ -155,12 +155,13 @@ public class MongoIdentityUserRepository : MongoDbRepository<IAbpIdentityMongoDb
         DateTime? minModifitionTime = null,
         CancellationToken cancellationToken = default)
     {
+        var upperFilter = filter?.ToUpperInvariant();
         return await (await GetMongoQueryableAsync(cancellationToken))
             .WhereIf<IdentityUser, IMongoQueryable<IdentityUser>>(
                 !filter.IsNullOrWhiteSpace(),
                 u =>
-                    u.UserName.Contains(filter) ||
-                    u.Email.Contains(filter) ||
+                    u.NormalizedUserName.Contains(upperFilter) ||
+                    u.NormalizedEmail.Contains(upperFilter) ||
                     (u.Name != null && u.Name.Contains(filter)) ||
                     (u.Surname != null && u.Surname.Contains(filter)) ||
                     (u.PhoneNumber != null && u.PhoneNumber.Contains(filter))
@@ -240,12 +241,13 @@ public class MongoIdentityUserRepository : MongoDbRepository<IAbpIdentityMongoDb
         DateTime? minModifitionTime = null,
         CancellationToken cancellationToken = default)
     {
+        var upperFilter = filter?.ToUpperInvariant();
         return await (await GetMongoQueryableAsync(cancellationToken))
             .WhereIf<IdentityUser, IMongoQueryable<IdentityUser>>(
                 !filter.IsNullOrWhiteSpace(),
                 u =>
-                    u.UserName.Contains(filter) ||
-                    u.Email.Contains(filter) ||
+                    u.NormalizedUserName.Contains(upperFilter) ||
+                    u.NormalizedEmail.Contains(upperFilter) ||
                     (u.Name != null && u.Name.Contains(filter)) ||
                     (u.Surname != null && u.Surname.Contains(filter)) ||
                     (u.PhoneNumber != null && u.PhoneNumber.Contains(filter))