diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index f96f85a9ce..bada6ba13d 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -39,6 +39,7 @@ jobs:
         name: Set up PDM
         with:
           python-version: ${{ inputs.python-version }}
+          version: ${{ inputs.python-version == "3.8" && "2.20.1" || "latest"}}
           allow-python-prereleases: false
           cache: true
           cache-dependency-path: |