diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index b4637912e..54dcd992e 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -17,7 +17,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        os: [ ubuntu-20.04, ubuntu-22.04, ubuntu-24.04, macos-13, macos-14, macos-15, windows-2019, windows-2022 ]
+        os: [ ubuntu-20.04, ubuntu-22.04, ubuntu-24.04, macos-13, macos-14, macos-15, windows-2019, windows-2022, windows-2025 ]
         ruby: [
           '1.9', '2.0', '2.1', '2.2', '2.3', '2.4', '2.5', '2.6', '2.7', '3.0', '3.1', '3.2', '3.3', '3.4', ruby-head,
           jruby, jruby-head,
@@ -30,6 +30,9 @@ jobs:
         - { os: windows-2022, ruby: mingw }
         - { os: windows-2022, ruby: mswin }
         - { os: windows-2022, ruby: ucrt  }
+        - { os: windows-2025, ruby: mingw }
+        - { os: windows-2025, ruby: mswin }
+        - { os: windows-2025, ruby: ucrt  }
         - { os: ubuntu-24.04, ruby: asan }
         exclude:
         # https://github.com/ruby/setup-ruby/issues/496
@@ -54,18 +57,22 @@ jobs:
         # Windows (note: previews are not available on Windows)
         - { os: windows-2019, ruby: '1.9' }
         - { os: windows-2022, ruby: '1.9' }
-        - { os: windows-2019, ruby: '3.4' } # 3.4.0-preview2
-        - { os: windows-2022, ruby: '3.4' } # 3.4.0-preview2
+        - { os: windows-2025, ruby: '1.9' }
         - { os: windows-2019, ruby: debug }
         - { os: windows-2022, ruby: debug }
+        - { os: windows-2025, ruby: debug }
         - { os: windows-2019, ruby: truffleruby }
         - { os: windows-2022, ruby: truffleruby }
+        - { os: windows-2025, ruby: truffleruby }
         - { os: windows-2019, ruby: truffleruby-head }
         - { os: windows-2022, ruby: truffleruby-head }
+        - { os: windows-2025, ruby: truffleruby-head }
         - { os: windows-2019, ruby: truffleruby+graalvm }
         - { os: windows-2022, ruby: truffleruby+graalvm }
+        - { os: windows-2025, ruby: truffleruby+graalvm }
         - { os: windows-2019, ruby: truffleruby+graalvm-head }
         - { os: windows-2022, ruby: truffleruby+graalvm-head }
+        - { os: windows-2025, ruby: truffleruby+graalvm-head }
 
     name: ${{ matrix.os }} ${{ matrix.ruby }}
     runs-on: ${{ matrix.os }}