diff --git a/composer.json b/composer.json
index 735264b9..b159c860 100644
--- a/composer.json
+++ b/composer.json
@@ -41,7 +41,7 @@
     "psr-4": {
       "Kiri\\": "core/",
       "Http\\": "http-helper/",
-      "Http\\Message": "http-message/",
+      "Http\\Message\\": "http-message/",
       "Server\\": "http-server/",
       "Console\\": "kiri-console/",
       "Gii\\": "kiri-gii/",