diff --git a/server/model/monitor.js b/server/model/monitor.js
index 48bd5a4cc..f99939170 100644
--- a/server/model/monitor.js
+++ b/server/model/monitor.js
@@ -470,10 +470,6 @@ class Monitor extends BeanModel {
         this.prometheus().remove();
     }
 
-    onDelete() {
-        this.prometheus().remove();
-    }
-
     prometheus() {
         return new Prometheus(this);
     }
diff --git a/server/server.js b/server/server.js
index fbf0a06e0..3e888c92a 100644
--- a/server/server.js
+++ b/server/server.js
@@ -738,7 +738,6 @@ exports.entryPage = "dashboard";
 
                 if (monitorID in monitorList) {
                     monitorList[monitorID].stop();
-                    monitorList[monitorID].onDelete();
                     delete monitorList[monitorID];
                 }