diff --git a/README.md b/README.md
index ea00a6a..1f2ca8d 100644
--- a/README.md
+++ b/README.md
@@ -5,9 +5,9 @@ mini mirror app for desktop.
 
 ## 更新履歴 - Change log
 
-### mini-mirror 0.3.1 (リリース日未定)
+### mini-mirror 0.3.1 (2018-10-20)
 
-- ?????????????????????
+- macOS 版にデジタル署名を追加した。
 
 ### mini-mirror 0.3.0 (2018-04-08)
 
diff --git a/package.json b/package.json
index 898e65e..9606d32 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "mini-mirror",
-  "version": "0.3.1-alpha.1+nb",
+  "version": "0.3.1",
   "description": "mini mirror app for desktop.",
   "private": true,
   "main": "index.html",