diff --git a/package.json b/package.json
index 54944a8..7fa6473 100644
--- a/package.json
+++ b/package.json
@@ -19,7 +19,7 @@
   ],
   "author": "SATO taichi <ryushi@gmail.com>",
   "dependencies": {
-    "istanbul": "~0.3.0",
+    "istanbul": "~0.4.5",
     "dateformat": "~1.0.6",
     "minimatch": "~0.3.0"
   },