diff --git a/extensions/amp-story/1.0/amp-story.js b/extensions/amp-story/1.0/amp-story.js
index 355162d71369..4d0b7defa76a 100644
--- a/extensions/amp-story/1.0/amp-story.js
+++ b/extensions/amp-story/1.0/amp-story.js
@@ -965,7 +965,7 @@ export class AmpStory extends AMP.BaseElement {
     }
 
     const lockOrientation =
-      screen.orientation.lock ||
+      screen.orientation?.lock ||
       screen.lockOrientation ||
       screen.mozLockOrientation ||
       screen.msLockOrientation ||