diff --git a/.github/workflows/doc.yml b/.github/workflows/doc.yml
index f0d6668..c67fb6f 100644
--- a/.github/workflows/doc.yml
+++ b/.github/workflows/doc.yml
@@ -13,7 +13,7 @@ jobs:
       - uses: actions/checkout@v3
       - uses: ruby/setup-ruby@v1
         with:
-          ruby-version: 3.1
+          ruby-version: ruby
       - name: Generate document
         run: gem install -N yard && yard doc
       - name: Publish Documentation on GitHub Pages