diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 6882117..d216d2a 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -14,6 +14,9 @@ jobs:
           - '2.6'
           - '2.7'
           - '3.0'
+          - '3.1'
+          - '3.2'
+          - '3.3'
     name: Run test with Ruby ${{ matrix.ruby }}
     steps:
       - uses: actions/checkout@v2