diff --git a/libcef/browser/native/browser_platform_delegate_native_mac.mm b/libcef/browser/native/browser_platform_delegate_native_mac.mm
index cba76107c..93130d61f 100644
--- a/libcef/browser/native/browser_platform_delegate_native_mac.mm
+++ b/libcef/browser/native/browser_platform_delegate_native_mac.mm
@@ -99,6 +99,7 @@
 }
 
 - (void)cleanup:(id)window {
+  [window_ setDelegate:nil];
   [self release];
 }