diff --git a/composer.json b/composer.json
index bc7dc96..1dc0bb4 100644
--- a/composer.json
+++ b/composer.json
@@ -23,7 +23,7 @@
         "ext-intl": "*"
     },
     "require-dev": {
-        "phpunit/phpunit": "7.5.20|9.5.0",
+        "phpunit/phpunit": "9.6.10",
         "sunrise/coding-standard": "1.0.0"
     },
     "autoload": {