diff --git a/packages/backend/src/server/api/index.ts b/packages/backend/src/server/api/index.ts
index da98a9df19..40ecd10ecd 100644
--- a/packages/backend/src/server/api/index.ts
+++ b/packages/backend/src/server/api/index.ts
@@ -12,6 +12,7 @@ import { Instances, AccessTokens, Users } from "@/models/index.js";
 import config from "@/config/index.js";
 import endpoints from "./endpoints.js";
 import compatibility from "./compatibility.js";
+import {koaBody} from "koa-body";
 import handler from "./api-handler.js";
 import signup from "./private/signup.js";
 import signin from "./private/signin.js";
@@ -35,6 +36,13 @@ app.use(async (ctx, next) => {
 	await next();
 });
 
+app.use(
+	koaBody({
+		json: false,
+		multipart: true
+	})
+);
+
 app.use(
 	bodyParser({
 		// リクエストが multipart/form-data でない限りはJSONだと見なす
diff --git a/packages/backend/src/server/index.ts b/packages/backend/src/server/index.ts
index 34ffa3c0e4..14c127e8ba 100644
--- a/packages/backend/src/server/index.ts
+++ b/packages/backend/src/server/index.ts
@@ -146,8 +146,7 @@ router.post("/oauth/token", koaBody({
 	multipart: true
 }), async (ctx) => {
 	const body: any = ctx.request.body;
-	//const BASE_URL = `${ctx.request.protocol}://${ctx.request.hostname}`;
-	const BASE_URL = "http://localhost:3000";
+	const BASE_URL = `${ctx.request.protocol}://${ctx.request.hostname}`;
 	const generator = (megalodon as any).default;
 	const client = generator('misskey', BASE_URL, null) as MegalodonInterface;
 	const m = body.code.match(/^[a-zA-Z0-9-]+/);