diff --git a/Packages/com.quabug.any-processor/CodeGen/Extension/Extensions.cs b/Packages/com.quabug.any-processor/CodeGen/Extension/Extensions.cs
index 78c5a37..f708f70 100644
--- a/Packages/com.quabug.any-processor/CodeGen/Extension/Extensions.cs
+++ b/Packages/com.quabug.any-processor/CodeGen/Extension/Extensions.cs
@@ -215,13 +215,20 @@ public static void ReplacePropertyGetterByFieldMethod(this PropertyDefinition pr
             //     IL_0001: ldfld        class [AnySerialize]AnySerialize.AnyValue`1<object> TestAnySerialize::_value
             //     IL_0006: callvirt     instance !0/*object*/ class [AnySerialize]AnySerialize.AnyValue`1<object>::get_Value()
             //     IL_000b: ret
+            
+            // after(value type)
+            //     IL_0000: ldarg.0      // this
+            //     IL_0001: ldflda       valuetype AnySerialize.AnyDateTime AnySerialize.A::Field
+            //     IL_0006: call         instance valuetype [netstandard]System.DateTime AnySerialize.AnyDateTime::get_Value()
+            //     IL_000b: ret
             var instructions = property.GetMethod!.Body!.Instructions;
             var getValueMethod = serializedField.FieldType!.GetMethodReference(fieldMethodName, logger);
             getValueMethod = property.Module!.ImportReference(getValueMethod!);
+            var isValueTypeField = serializedField.FieldType.IsValueType;
             instructions!.Clear();
             instructions.Add(Instruction.Create(OpCodes.Ldarg_0));
-            instructions.Add(Instruction.Create(OpCodes.Ldfld, serializedField));
-            instructions.Add(Instruction.Create(OpCodes.Callvirt, getValueMethod!));
+            instructions.Add(Instruction.Create(isValueTypeField ? OpCodes.Ldflda : OpCodes.Ldfld, serializedField));
+            instructions.Add(Instruction.Create(isValueTypeField ? OpCodes.Call : OpCodes.Callvirt, getValueMethod!));
             instructions.Add(Instruction.Create(OpCodes.Ret));
         }
         
diff --git a/Packages/com.quabug.any-serialize/CodeGen/Extension.cs b/Packages/com.quabug.any-serialize/CodeGen/Extension.cs
index 4681331..ce855d4 100644
--- a/Packages/com.quabug.any-serialize/CodeGen/Extension.cs
+++ b/Packages/com.quabug.any-serialize/CodeGen/Extension.cs
@@ -13,9 +13,11 @@ public static class Extension
         public static TypeReference? CreateConcreteTypeFrom(this Container container, TypeReference type)
         {
             var def = type.Resolve();
-            if (def == null || def.IsAbstract || def.GetConstructors()!.FirstOrDefault(ctor => !ctor.HasParameters) == null) return null;
+            if (def == null) return null;
+            if (def.IsAbstract) return null;
+            if (!def.IsValueType && def.GetConstructors()!.FirstOrDefault(ctor => !ctor.HasParameters) == null) return null;
             if (type.IsConcreteType()) return type;
-            
+
             if (type is not GenericInstanceType genericType)
                 throw new ArgumentException($"{nameof(type)}({type}) must be a {nameof(GenericInstanceType)}", nameof(type));