diff --git a/.github/workflows/rdoc.yml b/.github/workflows/rdoc.yml
index 21d18dbe..a06a6d7c 100644
--- a/.github/workflows/rdoc.yml
+++ b/.github/workflows/rdoc.yml
@@ -27,7 +27,7 @@ jobs:
       - uses: actions/configure-pages@v5
       - uses: ruby/setup-ruby@v1
         with:
-          ruby-version: "3.3"
+          ruby-version: "4.0"
           bundler-cache: true
       - run: bundle exec rdoc
       - uses: actions/upload-pages-artifact@v4
diff --git a/Gemfile b/Gemfile
index 767e9a4d..b9403792 100644
--- a/Gemfile
+++ b/Gemfile
@@ -12,7 +12,7 @@ group :test do
 end
 
 group :development do
-  gem "rdoc", "6.15.1"
+  gem "rdoc", "7.0.3"
 
   gem "rubocop", "1.59.0", require: false
   gem "rubocop-minitest", "0.34.5", require: false