diff --git a/Assets/VRM/Editor/Format/VRMSampleCopy.cs b/Assets/VRM/Editor/Format/VRMSampleCopy.cs
index 028d90ce1..9724cbce1 100644
--- a/Assets/VRM/Editor/Format/VRMSampleCopy.cs
+++ b/Assets/VRM/Editor/Format/VRMSampleCopy.cs
@@ -1,11 +1,30 @@
 using System;
 using System.IO;
+using System.Linq;
 using UnityEngine;
 
 namespace VRM
 {
     public static class VRMSampleCopy
     {
+        struct CopyInfo
+        {
+            public string Src;
+            public string Dst;
+
+            public CopyInfo(string src, string dst)
+            {
+                Src = src;
+                Dst = dst;
+            }
+        }
+
+        static CopyInfo[] CopyList = new CopyInfo[]{
+            new CopyInfo(Path.Combine(Application.dataPath, "VRM_Samples"), Path.Combine(Application.dataPath, "VRM/Samples~")),
+            new CopyInfo(Path.Combine(Application.dataPath, "VRM10_Samples"), Path.Combine(Application.dataPath, "VRM10/Samples~")),
+            new CopyInfo(Path.Combine(Application.dataPath, "UniGLTF_Samples"), Path.Combine(Application.dataPath, "UniGLTF/Samples~")),
+        };
+
         /// <summary>
         /// Assets/VRM_Samples
         /// を
@@ -24,9 +43,10 @@ namespace VRM
         /// </summary>
         public static void Execute()
         {
-            Copy(Path.Combine(Application.dataPath, "VRM_Samples"), Path.Combine(Application.dataPath, "VRM/Samples~"));
-            Copy(Path.Combine(Application.dataPath, "VRM10_Samples"), Path.Combine(Application.dataPath, "VRM10/Samples~"));
-            Copy(Path.Combine(Application.dataPath, "UniGLTF_Samples"), Path.Combine(Application.dataPath, "UniGLTF/Samples~"));
+            foreach (var info in CopyList)
+            {
+                Copy(info.Src, info.Dst);
+            }
         }
 
         static void Copy(string srcDir, string dstDir)
@@ -61,5 +81,61 @@ namespace VRM
                 throw new FileNotFoundException(src);
             }
         }
+
+        public static bool Validate()
+        {
+            return CopyList.All(x => _Validate(x.Src, x.Dst));
+        }
+
+        static bool _Validate(string src, string dst)
+        {
+            if (Directory.Exists(src))
+            {
+                if (!Directory.Exists(dst))
+                {
+                    Debug.LogError($"{dst} not exists");
+                    return false;
+
+                }
+                var list = Directory.EnumerateFileSystemEntries(dst).Select(x => x.Substring(dst.Length + 1)).ToList();
+                foreach (var child in Directory.EnumerateFileSystemEntries(src))
+                {
+                    if (!_Validate(child, Path.Combine(dst, Path.GetFileName(child)).Replace("\\", "/")))
+                    {
+                        return false;
+                    }
+                    var rel = child.Substring(src.Length + 1);
+                    list.Remove(rel);
+                }
+                if (list.Count > 0)
+                {
+                    var remain = string.Join(",", list);
+                    Debug.LogError($"only dst: {remain}");
+                    return false;
+                }
+                return true;
+            }
+            else if (File.Exists(src))
+            {
+                // same file
+                if (!File.Exists(dst))
+                {
+                    Debug.LogError($"{dst} not exists");
+                    return false;
+                }
+                if (!File.ReadAllBytes(src).SequenceEqual(File.ReadAllBytes(dst)))
+                {
+                    Debug.LogError($"{src} != {dst}");
+                    return false;
+                }
+                return true;
+            }
+            else
+            {
+                // throw new FileNotFoundException(src);
+                Debug.LogError($"dir nor file");
+                return false;
+            }
+        }
     }
 }
diff --git a/Assets/VRM/Editor/VRMExportUnityPackage.cs b/Assets/VRM/Editor/VRMExportUnityPackage.cs
index 4b43eac49..532809479 100644
--- a/Assets/VRM/Editor/VRMExportUnityPackage.cs
+++ b/Assets/VRM/Editor/VRMExportUnityPackage.cs
@@ -187,6 +187,11 @@ namespace VRM.DevOnly.PackageExporter
 
         public static void CreateUnityPackages(string outputDir)
         {
+            if (!VRMSampleCopy.Validate())
+            {
+                throw new Exception("SampleCopy is not same !");
+            }
+
             {
                 var packages = new[]{
                     // VRM