diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index cf428755..e82642aa 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -61,7 +61,7 @@ jobs:
       uses: actions/cache@v2
       with:
         path: vendor
-        key: ${{ runner.os }}-php-${{ hashFiles('**/composer.lock') }}
+        key: ${{ runner.os }}-php-${{ matrix.php-version }}-${{ hashFiles('**/composer.lock') }}
         restore-keys: |
           ${{ runner.os }}-php-${{ matrix.php-version }}-