diff --git a/modules/EasyAbp.EShop.Products/src/EasyAbp.EShop.Products.Domain/EasyAbp/EShop/Products/Products/AttributeOptionIdsSerializer.cs b/modules/EasyAbp.EShop.Products/src/EasyAbp.EShop.Products.Domain/EasyAbp/EShop/Products/Products/AttributeOptionIdsSerializer.cs
index 132fb3fa..22891048 100644
--- a/modules/EasyAbp.EShop.Products/src/EasyAbp.EShop.Products.Domain/EasyAbp/EShop/Products/Products/AttributeOptionIdsSerializer.cs
+++ b/modules/EasyAbp.EShop.Products/src/EasyAbp.EShop.Products.Domain/EasyAbp/EShop/Products/Products/AttributeOptionIdsSerializer.cs
@@ -23,6 +23,11 @@ namespace EasyAbp.EShop.Products.Products
 
         public Task<string> SerializeAsync(IEnumerable<Guid> attributeOptionIds)
         {
+            if (attributeOptionIds == null)
+            {
+                return Task.FromResult(string.Empty);
+            }
+
             return Task.FromResult(_jsonSerializer.Serialize(attributeOptionIds.OrderBy(x => x)));
         }