diff --git a/.github/workflows/wpt.yml b/.github/workflows/wpt.yml
index 3fe78fc4..a3416928 100644
--- a/.github/workflows/wpt.yml
+++ b/.github/workflows/wpt.yml
@@ -41,8 +41,8 @@ jobs:
   wpt:
     name: web platform tests
 
-    # Don't run the CI with draft PR.
-    if: github.event.pull_request.draft == false
+    # Only for PR without draft.
+    if: github.event_name == 'pull_request' && github.event.pull_request.draft == false
 
     runs-on: ubuntu-latest