diff --git a/src/vs/base/common/cancellation.ts b/src/vs/base/common/cancellation.ts
index 233c19fe7d787d04ae2356e3212e2cbb38bfee5d..6797298bd8b5f292df0cd4ad4e1561e2eb525b73 100644
--- a/src/vs/base/common/cancellation.ts
+++ b/src/vs/base/common/cancellation.ts
@@ -45,6 +45,7 @@ class MutableToken implements CancellationToken {
 			this._isCancelled = true;
 			if (this._emitter) {
 				this._emitter.fire(undefined);
+				this._emitter.dispose();
 				this._emitter = undefined;
 			}
 		}