diff --git a/.github/workflows/rspec.yml b/.github/workflows/rspec.yml
index 005ae48..72de732 100644
--- a/.github/workflows/rspec.yml
+++ b/.github/workflows/rspec.yml
@@ -12,7 +12,7 @@ jobs:
       fail-fast: false
       matrix:
         ruby: ['2.0', '2.1', '2.2', '2.3', '2.4', '2.5', '2.6', '2.7', '3.0', '3.1', '3.2', '3.3']
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-20.04
     steps:
       - uses: actions/checkout@v4
       - uses: ruby/setup-ruby@v1