diff --git a/package.json b/package.json
index 118d2bb..f91c61a 100644
--- a/package.json
+++ b/package.json
@@ -67,7 +67,7 @@
     "eslint-plugin-standard": "^3.0.1",
     "husky": "^0.14.3",
     "koaton-exporter": "^1.2.1",
-    "mocha": "^4.0.1",
+    "mocha": "^5.2.0",
     "npm-run-all": "^4.1.1",
     "nyc": "11.4.1",
     "ps-tree": "^1.1.0"