diff --git a/src/rtmt/rtmt.ts b/src/rtmt/rtmt.ts
index efb6b70..bc04659 100644
--- a/src/rtmt/rtmt.ts
+++ b/src/rtmt/rtmt.ts
@@ -4,4 +4,5 @@ export type OnMessage = (message : Object) => any
 export interface RTMT{
     sendMessage : (channel : string, message : Object) => any
     listenMessage : (channel : string, callback : OnMessage) => any
+    unlistenMessage : (channel : string, callback : OnMessage) => any
 }
\ No newline at end of file
diff --git a/src/rtmt/rtmt_websocket.ts b/src/rtmt/rtmt_websocket.ts
index 3f93536..180d3c2 100644
--- a/src/rtmt/rtmt_websocket.ts
+++ b/src/rtmt/rtmt_websocket.ts
@@ -1,12 +1,12 @@
 import { decode, encode } from "./encode_decode_message";
 import { Bytes, OnMessage, RTMT } from "./rtmt";
-import { server } from "../service/http_service";
 import { channel_ping, channel_pong } from "../const/channel_names";
+import { server } from "../const/config";
 
 const PING_INTERVAL = 15000, PING_INTERVAL_BUFFER_TIME = 1000;
 
 export class RTMTWS implements RTMT {
-  private messageChannels: Map<String, OnMessage>;
+  private messageChannels: Map<String, OnMessage | undefined>;
   private ws: WebSocket;
 
   private pingTimeout?: number = undefined;
@@ -69,10 +69,16 @@ export class RTMTWS implements RTMT {
     this.ws.send(data);
   }
 
+  // todo: support multible listeners
   listenMessage(channel: string, callback: OnMessage) {
     this.messageChannels.set(channel, callback);
   }
 
+  // todo: support multible listeners
+  unlistenMessage(channel : string, callback : OnMessage) {
+    this.messageChannels.set(channel, undefined);
+  }
+
   onWebSocketMessage(rtmt: RTMTWS, event: MessageEvent) {
     const { channel, message } = decode(event.data);
     rtmt.onMessage(channel, message);