diff --git a/.github/workflows/microsoft-backport.yml b/.github/workflows/microsoft-backport.yml
index e970d331bae6..9d19efb82643 100644
--- a/.github/workflows/microsoft-backport.yml
+++ b/.github/workflows/microsoft-backport.yml
@@ -6,6 +6,7 @@ on:
   issue_comment:
     types: [created]
   pull_request:
+    branches: [main]
     types: [synchronize]
 
 permissions: