diff --git a/Assets/VRM10/Runtime/IO/Vrm10Exporter.cs b/Assets/VRM10/Runtime/IO/Vrm10Exporter.cs
index bd20f8cb4..3f0159365 100644
--- a/Assets/VRM10/Runtime/IO/Vrm10Exporter.cs
+++ b/Assets/VRM10/Runtime/IO/Vrm10Exporter.cs
@@ -14,7 +14,7 @@ namespace UniVRM10
         public const string VRM_SPEC_VERSION = "1.0-beta";
         public const string SPRINGBONE_SPEC_VERSION = "1.0-beta";
         public const string NODE_CONSTRAINT_SPEC_VERSION = "1.0-beta";
-        public const string MTOON_SPEC_VERSION = "1.0-draft";
+        public const string MTOON_SPEC_VERSION = "1.0-beta";
 
         public const string LICENSE_URL_JA = "https://vrm.dev/licenses/1.0/";
         public const string LICENSE_URL_EN = "https://vrm.dev/licenses/1.0/en/";