diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index baed303e4..847ba2af3 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -22,7 +22,6 @@ jobs:
           - {os: ubuntu-20.04, cc: clang, cxx: clang++}
           - {os: macos-latest, cc: clang, cxx: clang++}
           - {os: macos-13, cc: clang, cxx: clang++}
-          - {os: macos-12, cc: clang, cxx: clang++}
           - {os: windows-latest, cc: gcc, cxx: g++, altname: "mingw-gcc"}
     env:
       MRUBY_CONFIG: ci/gcc-clang