diff --git a/.github/workflows/pypi-publish.yml b/.github/workflows/pypi-publish.yml
index dac33fe31..7a06c4867 100644
--- a/.github/workflows/pypi-publish.yml
+++ b/.github/workflows/pypi-publish.yml
@@ -21,7 +21,7 @@ jobs:
       run: |
         pip install .
         RELEASE_VER=${GITHUB_REF#refs/*/}
-        PACKAGE_VER="v`python -c "import optax; print(optax.__version__)"`"
+        PACKAGE_VER="v`python -c 'import optax; print(optax.__version__)'`"
         if [ $RELEASE_VER != $PACKAGE_VER ]
         then
           echo "package ver. ($PACKAGE_VER) != release ver. ($RELEASE_VER)"; exit 1