diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index ff3bdcd8..b2419b39 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -20,11 +20,6 @@ jobs:
           - '3.0'
           - '2.7'
           - '2.6'
-          - '2.5'
-          - '2.4'
-          - '2.3'
-          - '2.2'
-          - '2.1'
     steps:
     - uses: actions/checkout@v2
     - uses: ruby/setup-ruby@v1