diff --git a/.github/workflows/lock.yaml b/.github/workflows/lock.yaml
index 7838fdbe82e..94f2600dac5 100644
--- a/.github/workflows/lock.yaml
+++ b/.github/workflows/lock.yaml
@@ -9,6 +9,7 @@ on:
 jobs:
   lock:
     runs-on: ubuntu-latest
+    if: ${{ github.repository == 'flutter/flutter' }}
     steps:
       - uses: dessant/lock-threads@486f7380c15596f92b724e4260e4981c68d6bde6
         with: