diff --git a/CHANGELOG.md b/CHANGELOG.md
index 9b09281bfab51e2fc03279b590b182c7ecd76350..0502e485c658018cfaafdad30243bfc8ccb2a25c 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -14,6 +14,7 @@ You should also include the user name that made the change.
 - ロールにアイコンを設定してユーザー名の横に表示できるように
 - feat: timeline page for non-login users
 - 実績の単なるラッキーの獲得確立を調整
+- Add Thai language support
 
 ### Bugfixes
 - fix(server): 自分のノートをお気に入りに登録しても実績解除される問題を修正
diff --git a/locales/index.js b/locales/index.js
index 92cd9b467c28670839eb07298c62c3c620d8eb1d..2248bb6ac976c9728a1164d7fa83b87fe1a098c3 100644
--- a/locales/index.js
+++ b/locales/index.js
@@ -34,6 +34,7 @@ const languages = [
 	'pt-PT',
 	'ru-RU',
 	'sk-SK',
+	'th-TH',
 	'ug-CN',
 	'uk-UA',
 	'vi-VN',