diff --git a/CHANGELOG.md b/CHANGELOG.md
index b629fa4611426fcd8b985aa1f8cdeed64c1fa3f6..5bfddbbc6df572112d25fe178dfe15b5722ea221 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -28,6 +28,7 @@ You should also include the user name that made the change.
 - Playのソースコード上限文字数を2倍に拡張
 - 付箋ウィジェットの高さを設定可能に
 - 配送先サーバーが410 Goneで応答してきた場合は自動で配送停止をするように
+- avatarBlurHash/bannerBlurHashの型をstringに限定
 
 ### Bugfixes
 - プロフィールで設定した情報が削除できない問題を修正
diff --git a/packages/backend/src/models/json-schema/user.ts b/packages/backend/src/models/json-schema/user.ts
index 8c61ee1f5f108205c4d0499c94d50666f8496879..e8a7212c5217785a28bec0b8a487d1ee931e1be6 100644
--- a/packages/backend/src/models/json-schema/user.ts
+++ b/packages/backend/src/models/json-schema/user.ts
@@ -29,7 +29,7 @@ export const packedUserLiteSchema = {
 			nullable: true, optional: false,
 		},
 		avatarBlurhash: {
-			type: 'any',
+			type: 'string',
 			nullable: true, optional: false,
 		},
 		isAdmin: {
@@ -93,7 +93,7 @@ export const packedUserDetailedNotMeOnlySchema = {
 			nullable: true, optional: false,
 		},
 		bannerBlurhash: {
-			type: 'any',
+			type: 'string',
 			nullable: true, optional: false,
 		},
 		isLocked: {