diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index bb104f9c..1bcdd6b8 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -4,6 +4,7 @@ on: [push, pull_request]
 
 jobs:
   job:
+    if: github.event_name == 'push' || github.event.pull_request.head.repo.full_name != github.repository
     strategy:
       fail-fast: false
       matrix: