diff --git a/Editor/Polymorphic/PolymorphicCodeGenerator.cs b/Editor/Polymorphic/PolymorphicCodeGenerator.cs
index 23d9c22..8a6a784 100644
--- a/Editor/Polymorphic/PolymorphicCodeGenerator.cs
+++ b/Editor/Polymorphic/PolymorphicCodeGenerator.cs
@@ -4,6 +4,7 @@ using System.IO;
 using System.Linq;
 using System.Text;
 using dnlib.DotNet.PolymorphicWriter;
+using HybridCLR.Editor.Installer;
 using HybridCLR.Editor.Template;
 
 public class PolymorphicCodeGenerator
@@ -214,6 +215,12 @@ public class PolymorphicCodeGenerator
 
     public void Generate()
     {
+        var installerController = new InstallerController();
+        if (installerController.PackageVersion.CompareTo("8.4.0") < 0)
+        {
+            throw new Exception("Polymorphic code generation requires com.code-philosophy.hybridclr package version 8.4.0 or higher.");
+        }
+
         CopyMetadataReaderHeader();
         GeneratePolymorphicDefs();
         GeneratePolymorphicDatas();