diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index 35e4cdb84a..ce97355045 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -9,7 +9,7 @@ jobs:
         runs-on: ubuntu-latest
         strategy:
             matrix:
-                php: [ "5.6", "7.0", "7.1", "7.2", "7.3", "7.4", "8.0", "8.1" ]
+                php: [ "7.0", "7.1", "7.2", "7.3", "7.4", "8.0", "8.1" ]
         name: PHP ${{matrix.php }} Unit Test
         steps:
             - uses: actions/checkout@v3
@@ -23,7 +23,7 @@ jobs:
                 timeout_minutes: 10
                 max_attempts: 3
                 command: composer install
-            - if: ${{ contains(fromJson('["5.6", "7.0", "7.1"]'), matrix.php)}}
+            - if: ${{ contains(fromJson('["7.0", "7.1"]'), matrix.php)}}
               name: Run PHPUnit Patches
               run: sh .github/apply-phpunit-patches.sh
             - name: Run Script
@@ -32,7 +32,7 @@ jobs:
         runs-on: ubuntu-latest
         strategy:
             matrix:
-                php: [ "5.6", "7.2" ]
+                php: [ "7.0", "7.2" ]
         name: PHP ${{matrix.php }} Unit Test Prefer Lowest
         steps:
             - uses: actions/checkout@v3
@@ -46,7 +46,7 @@ jobs:
                 timeout_minutes: 10
                 max_attempts: 3
                 command: composer update --prefer-lowest
-            - if: ${{ matrix.php == '5.6' }}
+            - if: ${{ matrix.php == '7.0' }}
               name: Run PHPUnit Patches
               run: sh .github/apply-phpunit-patches.sh
             - name: Run Script
diff --git a/composer.json b/composer.json
index 541c6716f4..97d79fc0ef 100644
--- a/composer.json
+++ b/composer.json
@@ -9,7 +9,7 @@
     "docs": "https://googleapis.github.io/google-auth-library-php/main/"
   },
   "require": {
-    "php": ">=5.6",
+    "php": "^7.0||^8.0",
     "firebase/php-jwt": "~5.0",
     "guzzlehttp/guzzle": "^6.2.1|^7.0",
     "guzzlehttp/psr7": "^1.7|^2.0",