diff --git a/CHANGELOG.md b/CHANGELOG.md
index 7c011b8c89..9ee5cfbbc4 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,4 +1,4 @@
-## Unreleased
+## 2026.5.2
 
 ### Note
 - config に `threadPoolSize` オプションが追加されました。
diff --git a/package.json b/package.json
index 2646b4bb27..54b3459c99 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
 	"name": "misskey",
-	"version": "2026.5.1",
+	"version": "2026.5.2-alpha.0",
 	"codename": "nasubi",
 	"repository": {
 		"type": "git",
diff --git a/packages/misskey-js/package.json b/packages/misskey-js/package.json
index 50d9f9b5b3..36538ada75 100644
--- a/packages/misskey-js/package.json
+++ b/packages/misskey-js/package.json
@@ -1,7 +1,7 @@
 {
 	"type": "module",
 	"name": "misskey-js",
-	"version": "2026.5.1",
+	"version": "2026.5.2-alpha.0",
 	"description": "Misskey SDK for JavaScript",
 	"license": "MIT",
 	"main": "./built/index.js",