diff --git a/Assets/VRM/UniGLTF/Editor/Serialization/ExtensionSerialization.cs b/Assets/VRM/UniGLTF/Editor/Serialization/ExtensionSerialization.cs
new file mode 100644
index 000000000..97b6d3d1f
--- /dev/null
+++ b/Assets/VRM/UniGLTF/Editor/Serialization/ExtensionSerialization.cs
@@ -0,0 +1,22 @@
+using System;
+using System.IO;
+
+namespace UniGLTF
+{
+    public class ExtensionSerialization : IValueSerialization
+    {
+        public Type ValueType => typeof(object);
+
+        public bool IsInline => true;
+
+        public void GenerateDeserializer(StreamWriter writer, string callName)
+        {
+            throw new System.NotImplementedException();
+        }
+
+        public string GenerateDeserializerCall(string callName, string argName)
+        {
+            return argName;
+        }
+    }
+}
diff --git a/Assets/VRM/UniGLTF/Editor/Serialization/ExtensionSerialization.cs.meta b/Assets/VRM/UniGLTF/Editor/Serialization/ExtensionSerialization.cs.meta
new file mode 100644
index 000000000..bd4cf7200
--- /dev/null
+++ b/Assets/VRM/UniGLTF/Editor/Serialization/ExtensionSerialization.cs.meta
@@ -0,0 +1,11 @@
+fileFormatVersion: 2
+guid: 827d441621713194c88a8c94b7b1c2f0
+MonoImporter:
+  externalObjects: {}
+  serializedVersion: 2
+  defaultReferences: []
+  executionOrder: 0
+  icon: {instanceID: 0}
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: 
diff --git a/Assets/VRM/UniGLTF/Editor/Serialization/FieldSerializationInfo.cs b/Assets/VRM/UniGLTF/Editor/Serialization/FieldSerializationInfo.cs
index f0236d6d4..00673acc6 100644
--- a/Assets/VRM/UniGLTF/Editor/Serialization/FieldSerializationInfo.cs
+++ b/Assets/VRM/UniGLTF/Editor/Serialization/FieldSerializationInfo.cs
@@ -126,6 +126,10 @@ namespace UniGLTF
             {
                 return new EnumIntSerialization(t, attr.EnumSerializationType);
             }
+            else if (t == typeof(object))
+            {
+                return new ExtensionSerialization();
+            }
 
             return new ObjectSerialization(t, path);
         }
diff --git a/Assets/VRM/UniGLTF/Editor/Serialization/ObjectSerialization.cs b/Assets/VRM/UniGLTF/Editor/Serialization/ObjectSerialization.cs
index 6f9d20da8..387e6156b 100644
--- a/Assets/VRM/UniGLTF/Editor/Serialization/ObjectSerialization.cs
+++ b/Assets/VRM/UniGLTF/Editor/Serialization/ObjectSerialization.cs
@@ -38,11 +38,6 @@ namespace UniGLTF
             m_fsi = t.GetFields(DeserializerGenerator.FIELD_FLAGS)
             .Where(x =>
             {
-                if (x.FieldType == typeof(object))
-                {
-                    // object. coannot serialize
-                    return false;
-                }
                 if (x.IsLiteral && !x.IsInitOnly)
                 {
                     // const
diff --git a/Assets/VRM/UniGLTF/Scripts/Format/ExtensionsAndExtras/KHR_texture_transform.cs b/Assets/VRM/UniGLTF/Scripts/Format/ExtensionsAndExtras/KHR_texture_transform.cs
index eb2564013..65dab1244 100644
--- a/Assets/VRM/UniGLTF/Scripts/Format/ExtensionsAndExtras/KHR_texture_transform.cs
+++ b/Assets/VRM/UniGLTF/Scripts/Format/ExtensionsAndExtras/KHR_texture_transform.cs
@@ -1,4 +1,6 @@
 using System;
+using System.Collections.Generic;
+using System.Linq;
 using UniJSON;
 
 namespace UniGLTF
@@ -22,6 +24,17 @@ namespace UniGLTF
         [ItemJsonSchema(Minimum = 0)]
         public int texCoord;
 
+        static IEnumerable<float> DeserializeFloat2(ListTreeNode<JsonValue> json)
+        {
+            if (json.Value.ValueType == ValueNodeType.Array)
+            {
+                foreach (var a in json.ArrayItems())
+                {
+                    yield return a.GetSingle();
+                }
+            }
+        }
+
         static glTF_KHR_texture_transform Deserialize(ListTreeNode<JsonValue> json)
         {
             var t = new glTF_KHR_texture_transform();
@@ -34,22 +47,25 @@ namespace UniGLTF
                     switch (key)
                     {
                         case nameof(offset):
-                            throw new NotImplementedException();
+                            t.offset = DeserializeFloat2(kv.Value).ToArray();
                             break;
+
                         case nameof(rotation):
-                            throw new NotImplementedException();
+                            t.rotation = kv.Value.GetSingle();
                             break;
+
                         case nameof(scale):
-                            throw new NotImplementedException();
+                            t.scale = DeserializeFloat2(kv.Value).ToArray();
                             break;
+
                         case nameof(texCoord):
-                            throw new NotImplementedException();
+                            t.texCoord = kv.Value.GetInt32();
                             break;
+
                         default:
                             throw new NotImplementedException();
                     }
                 }
-
             }
 
             return t;