diff --git a/packages/zone.js/lib/common/timers.ts b/packages/zone.js/lib/common/timers.ts
index 50889dbc0e..e1d68b5a6d 100644
--- a/packages/zone.js/lib/common/timers.ts
+++ b/packages/zone.js/lib/common/timers.ts
@@ -55,7 +55,7 @@ export function patchTimer(window: any, setName: string, cancelName: string, nam
   }
 
   function clearTask(task: Task) {
-    return clearNative!((<TimerOptions>task.data).handleId);
+    return clearNative!.call(window, (<TimerOptions>task.data).handleId);
   }
 
   setNative =
diff --git a/packages/zone.js/test/common/setTimeout.spec.ts b/packages/zone.js/test/common/setTimeout.spec.ts
index ed62e586ae..7d4f31eb6a 100644
--- a/packages/zone.js/test/common/setTimeout.spec.ts
+++ b/packages/zone.js/test/common/setTimeout.spec.ts
@@ -6,7 +6,9 @@
  * found in the LICENSE file at https://angular.io/license
  */
 
+import {patchTimer} from '../../lib/common/timers';
 import {isNode, zoneSymbol} from '../../lib/common/utils';
+
 declare const global: any;
 const wtfMock = global.wtfMock;
 
@@ -56,6 +58,25 @@ describe('setTimeout', function() {
     });
   });
 
+  it('should call native clearTimeout with the correct context', function() {
+    // since clearTimeout has been patched already, we can not test `clearTimeout` directly
+    // we will fake another API patch to test
+    let context: any = null;
+    const fakeGlobal = {
+      setTimeout: function() {
+        return 1;
+      },
+      clearTimeout: function(id: number) {
+        context = this;
+      }
+    };
+    patchTimer(fakeGlobal, 'set', 'clear', 'Timeout')
+    const cancelId = fakeGlobal.setTimeout();
+    const m = fakeGlobal.clearTimeout;
+    m.call({}, cancelId);
+    expect(context).toBe(fakeGlobal);
+  });
+
   it('should allow cancelation of fns registered with setTimeout after invocation', function(done) {
     const testZone = Zone.current.fork((Zone as any)['wtfZoneSpec']).fork({name: 'TestZone'});
     testZone.run(() => {