diff --git a/locales/ja.json b/locales/ja.json
index 0967ef424b..a76ec9f48a 100644
--- a/locales/ja.json
+++ b/locales/ja.json
@@ -1 +1,3 @@
-{}
+{
+    "password_too_simple_1": "パスワードは少なくとも8文字必要です"
+}