diff --git a/CHANGELOG.md b/CHANGELOG.md
index cddd9f1ad7..b986273d0d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -39,6 +39,7 @@
   (Cherry-picked from https://activitypub.software/TransFem-org/Sharkey/-/merge_requests/711)
 - Fix: FTT無効時にユーザーリストタイムラインが使用できない問題を修正  
   (Cherry-picked from https://activitypub.software/TransFem-org/Sharkey/-/merge_requests/709)
+- Enhance: リモートユーザーの照会をオリジナルにリダイレクトするように
 
 ### Misskey.js
 - Fix: Stream初期化時、別途WebSocketを指定する場合の型定義を修正
diff --git a/packages/backend/src/server/ActivityPubServerService.ts b/packages/backend/src/server/ActivityPubServerService.ts
index 3255d64621..ba2342b630 100644
--- a/packages/backend/src/server/ActivityPubServerService.ts
+++ b/packages/backend/src/server/ActivityPubServerService.ts
@@ -29,6 +29,7 @@ import { UserEntityService } from '@/core/entities/UserEntityService.js';
 import { bindThis } from '@/decorators.js';
 import { IActivity } from '@/core/activitypub/type.js';
 import { isQuote, isRenote } from '@/misc/is-renote.js';
+import * as Acct from '@/misc/acct.js';
 import type { FastifyInstance, FastifyRequest, FastifyReply, FastifyPluginOptions, FastifyBodyParser } from 'fastify';
 import type { FindOptionsWhere } from 'typeorm';
 
@@ -486,6 +487,16 @@ export class ActivityPubServerService {
 			return;
 		}
 
+		// リモートだったらリダイレクト
+		if (user.host != null) {
+			if (user.uri == null || this.utilityService.isSelfHost(user.host)) {
+				reply.code(500);
+				return;
+			}
+			reply.redirect(user.uri, 301);
+			return;
+		}
+
 		reply.header('Cache-Control', 'public, max-age=180');
 		this.setResponseType(request, reply);
 		return (this.apRendererService.addContext(await this.apRendererService.renderPerson(user as MiLocalUser)));
@@ -654,19 +665,20 @@ export class ActivityPubServerService {
 
 			const user = await this.usersRepository.findOneBy({
 				id: userId,
-				host: IsNull(),
 				isSuspended: false,
 			});
 
 			return await this.userInfo(request, reply, user);
 		});
 
-		fastify.get<{ Params: { user: string; } }>('/@:user', { constraints: { apOrHtml: 'ap' } }, async (request, reply) => {
+		fastify.get<{ Params: { acct: string; } }>('/@:acct', { constraints: { apOrHtml: 'ap' } }, async (request, reply) => {
 			vary(reply.raw, 'Accept');
 
+			const acct = Acct.parse(request.params.acct);
+
 			const user = await this.usersRepository.findOneBy({
-				usernameLower: request.params.user.toLowerCase(),
-				host: IsNull(),
+				usernameLower: acct.username,
+				host: acct.host ?? IsNull(),
 				isSuspended: false,
 			});
 
diff --git a/packages/backend/test/e2e/fetch-resource.ts b/packages/backend/test/e2e/fetch-resource.ts
index 7efd688ec2..8ea4cb9800 100644
--- a/packages/backend/test/e2e/fetch-resource.ts
+++ b/packages/backend/test/e2e/fetch-resource.ts
@@ -230,6 +230,7 @@ describe('Webリソース', () => {
 				path: path('xxxxxxxxxx'),
 				type: HTML,
 			}));
+			test.todo('HTMLとしてGETできる。(リモートユーザーでもリダイレクトせず)');
 		});
 
 		describe.each([
@@ -249,6 +250,7 @@ describe('Webリソース', () => {
 				path: path('xxxxxxxxxx'),
 				accept,
 			}));
+			test.todo('はオリジナルにリダイレクトされる。(リモートユーザー)');
 		});
 	});