diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 899d9269d..5f74e4da3 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -19,8 +19,8 @@ jobs:
           python-version: ${{ matrix.python-version }}
 
       - name: Install packages
-        run: pip install tox tox-gh-actions==3.0.0a2
+        run: pip install tox==4.0.0b1 tox-gh-actions==3.0.0a2
 
       # see: https://github.com/ymyzk/tox-gh-actions
       - name: Run tests
-        run: tox
+        run: tox4