diff --git a/package.json b/package.json
index 7167f86..c7c7785 100644
--- a/package.json
+++ b/package.json
@@ -29,7 +29,7 @@
     "karma-mocha-reporter": "^2.2.3",
     "karma-power-assert": "^1.0.0",
     "karma-sinon": "^1.0.5",
-    "mocha": "^3.1.0",
+    "mocha": "^4.0.0",
     "power-assert": "^1.4.4",
     "sinon": "^3.0.0"
   },