diff --git a/framework/src/Volo.Abp.Core/Volo/Abp/DependencyInjection/AutoRegistrationHelper.cs b/framework/src/Volo.Abp.Core/Volo/Abp/DependencyInjection/AutoRegistrationHelper.cs
index dd8795855e..7d0ce0a39e 100644
--- a/framework/src/Volo.Abp.Core/Volo/Abp/DependencyInjection/AutoRegistrationHelper.cs
+++ b/framework/src/Volo.Abp.Core/Volo/Abp/DependencyInjection/AutoRegistrationHelper.cs
@@ -8,7 +8,7 @@ namespace Volo.Abp.DependencyInjection
 {
     public static class AutoRegistrationHelper
     {
-        public static IEnumerable<Type> GetExposedServices(IServiceCollection services, Type type)
+        public static List<Type> GetExposedServices(IServiceCollection services, Type type)
         {
             var typeInfo = type.GetTypeInfo();
 
@@ -23,10 +23,10 @@ namespace Volo.Abp.DependencyInjection
                 return customExposedServices;
             }
 
-            return GetDefaultExposedServices(services, type);
+            return GetDefaultExposedServices(type);
         }
 
-        private static IEnumerable<Type> GetDefaultExposedServices(IServiceCollection services, Type type)
+        private static List<Type> GetDefaultExposedServices(Type type)
         {
             var serviceTypes = new List<Type>();
 
@@ -47,16 +47,6 @@ namespace Volo.Abp.DependencyInjection
                 }
             }
 
-            var exposeActions = services.GetExposingActionList();
-            if (exposeActions.Any())
-            {
-                var args = new OnServiceExposingContext(type, serviceTypes);
-                foreach (var action in services.GetExposingActionList())
-                {
-                    action(args);
-                }
-            }
-
             return serviceTypes;
         }
     }
diff --git a/framework/src/Volo.Abp.Core/Volo/Abp/DependencyInjection/DefaultConventionalRegistrar.cs b/framework/src/Volo.Abp.Core/Volo/Abp/DependencyInjection/DefaultConventionalRegistrar.cs
index 19740d6ab6..b76c37682d 100644
--- a/framework/src/Volo.Abp.Core/Volo/Abp/DependencyInjection/DefaultConventionalRegistrar.cs
+++ b/framework/src/Volo.Abp.Core/Volo/Abp/DependencyInjection/DefaultConventionalRegistrar.cs
@@ -1,4 +1,6 @@
 using System;
+using System.Collections.Generic;
+using System.Linq;
 using System.Reflection;
 using JetBrains.Annotations;
 using Microsoft.Extensions.DependencyInjection;
@@ -24,7 +26,11 @@ namespace Volo.Abp.DependencyInjection
                 return;
             }
 
-            foreach (var serviceType in AutoRegistrationHelper.GetExposedServices(services, type))
+            var serviceTypes = AutoRegistrationHelper.GetExposedServices(services, type);
+
+            TriggerServiceExposing(services, type, serviceTypes);
+
+            foreach (var serviceType in serviceTypes)
             {
                 var serviceDescriptor = ServiceDescriptor.Describe(serviceType, type, lifeTime.Value);
 
@@ -43,6 +49,19 @@ namespace Volo.Abp.DependencyInjection
             }
         }
 
+        protected virtual void TriggerServiceExposing(IServiceCollection services, Type type, List<Type> serviceTypes)
+        {
+            var exposeActions = services.GetExposingActionList();
+            if (exposeActions.Any())
+            {
+                var args = new OnServiceExposingContext(type, serviceTypes);
+                foreach (var action in exposeActions)
+                {
+                    action(args);
+                }
+            }
+        }
+
         protected virtual bool IsConventionalRegistrationDisabled(Type type)
         {
             return type.IsDefined(typeof(DisableConventionalRegistrationAttribute), true);