diff --git a/.github/workflows/test_simpleaf.yml b/.github/workflows/test_simpleaf.yml
index 8324c29..f896ff4 100644
--- a/.github/workflows/test_simpleaf.yml
+++ b/.github/workflows/test_simpleaf.yml
@@ -14,7 +14,7 @@ jobs:
     if: "!contains(github.event.head_commit.message, 'skip ci')"
     strategy:
       matrix:
-        os: [ubuntu-latest, macos-latest]
+        os: [ubuntu-latest, macos-13]
     runs-on: ${{ matrix.os }}
     steps:
       - name: Checkout repository