diff --git a/.github/workflows/codeql.yml b/.github/workflows/codeql.yml
index f1142d5..b6de896 100644
--- a/.github/workflows/codeql.yml
+++ b/.github/workflows/codeql.yml
@@ -2,6 +2,8 @@ name: Download and run codeQL
 
 on:
   pull_request:
+    branches:
+      - 'master'
   push:
     branches:
       - 'master'