diff --git a/mirai-core-api/src/commonMain/kotlin/internal/message/MessageSerializersImpl.kt b/mirai-core-api/src/commonMain/kotlin/internal/message/MessageSerializersImpl.kt
index ac472e1fb..232512fdf 100644
--- a/mirai-core-api/src/commonMain/kotlin/internal/message/MessageSerializersImpl.kt
+++ b/mirai-core-api/src/commonMain/kotlin/internal/message/MessageSerializersImpl.kt
@@ -131,7 +131,6 @@ private val builtInSerializersModule by lazy {
             subclass(MusicShare::class, MusicShare.serializer())
 
             subclass(Dice::class, Dice.serializer())
-            subclass(UnsupportedMessage::class, UnsupportedMessage.Serializer)
         }