diff --git a/Src/Asp.NetCore2/SqlSugar/Abstract/SaveableProvider/Storageable.cs b/Src/Asp.NetCore2/SqlSugar/Abstract/SaveableProvider/Storageable.cs
index 3d258e656..a5f2e1655 100644
--- a/Src/Asp.NetCore2/SqlSugar/Abstract/SaveableProvider/Storageable.cs
+++ b/Src/Asp.NetCore2/SqlSugar/Abstract/SaveableProvider/Storageable.cs
@@ -551,6 +551,10 @@ namespace SqlSugar
                 foreach (var item in whereColumns)
                 {
                     var value = item.PropertyInfo.GetValue(dataItem.Item, null);
+                    if (value is string str&&str=="null") 
+                    {
+                        value = $"[null]";
+                    }
                     if (value != null&&value.GetType().IsEnum()) 
                     {
                         if (this.Context.CurrentConnectionConfig.MoreSettings?.TableEnumIsString == true)
diff --git a/Src/Asp.NetCore2/SqlSugar/Abstract/SqlBuilderProvider/SqlBuilderProvider_Condition.cs b/Src/Asp.NetCore2/SqlSugar/Abstract/SqlBuilderProvider/SqlBuilderProvider_Condition.cs
index 2d7daa13f..ab4b7c587 100644
--- a/Src/Asp.NetCore2/SqlSugar/Abstract/SqlBuilderProvider/SqlBuilderProvider_Condition.cs
+++ b/Src/Asp.NetCore2/SqlSugar/Abstract/SqlBuilderProvider/SqlBuilderProvider_Condition.cs
@@ -389,7 +389,7 @@ namespace SqlSugar
             {
                 if (item.FieldValue == "[null]")
                 {
-                    item.FieldValue = "'null'";
+                    item.FieldValue = "null";
                 }
                 builder.AppendFormat(temp, type, item.FieldName.ToSqlFilter(), "=", parameterName);
                 parameters.Add(new SugarParameter(parameterName, GetFieldValue(item)));