diff --git a/.github/workflows/os-test.yml b/.github/workflows/os-test.yml
index 6dfac95..4c410ea 100644
--- a/.github/workflows/os-test.yml
+++ b/.github/workflows/os-test.yml
@@ -19,10 +19,8 @@ jobs:
           - windows-2019
           - ubuntu-22.04
           - ubuntu-20.04
-          - ubuntu-18.04
           - macos-12
           - macos-11
-          - macos-10.15
     runs-on: ${{ matrix.os }}
     steps:
       - uses: actions/checkout@v3