diff --git a/composer.json b/composer.json
index d6d42c8..30d022f 100644
--- a/composer.json
+++ b/composer.json
@@ -31,7 +31,7 @@
         "symfony/css-selector": "^3.0",
         "symfony/asset": "^3.2",
         "symfony/templating": "^3.2",
-        "phpunit/phpunit": "^5.7",
+        "phpunit/phpunit": "^6.0",
         "sebastian/recursion-context": "~2.0",
         "sebastian/exporter": "~2.0",
         "doctrine/doctrine-bundle": "^1.5",