diff --git a/.config/example.yml b/.config/example.yml
index d69b1cba4f..92b8726623 100644
--- a/.config/example.yml
+++ b/.config/example.yml
@@ -30,9 +30,6 @@ url: https://example.tld/
 # The port that your Misskey server should listen on.
 port: 3000
 
-# The hostname or address to listen on (default: all)
-#host: "127.0.0.1"
-
 #   ┌──────────────────────────┐
 #───┘ PostgreSQL configuration └────────────────────────────────
 
diff --git a/packages/backend/src/boot/master.ts b/packages/backend/src/boot/master.ts
index 008f9ec587..f5d936fadf 100644
--- a/packages/backend/src/boot/master.ts
+++ b/packages/backend/src/boot/master.ts
@@ -78,7 +78,7 @@ export async function masterMain() {
 		await spawnWorkers(config.clusterLimit);
 	}
 
-	bootLogger.succ(`Now listening on ${config.host ? `[${config.host}]:` : ''}${config.port} for ${config.url}`, null, true);
+	bootLogger.succ(`Now listening on port ${config.port} on ${config.url}`, null, true);
 }
 
 function showEnvironment(): void {
diff --git a/packages/backend/src/config.ts b/packages/backend/src/config.ts
index 0572002239..73f45e92e1 100644
--- a/packages/backend/src/config.ts
+++ b/packages/backend/src/config.ts
@@ -15,7 +15,6 @@ export type Source = {
 	feedback_url?: string;
 	url: string;
 	port: number;
-	host: string;
 	disableHsts?: boolean;
 	db: {
 		host: string;
@@ -126,7 +125,6 @@ export function loadConfig() {
 	config.url = url.origin;
 
 	config.port = config.port ?? parseInt(process.env.PORT ?? '', 10);
-	config.host = config.host ?? process.env.HOST;
 
 	mixin.version = meta.version;
 	mixin.host = url.host;
diff --git a/packages/backend/src/server/ServerService.ts b/packages/backend/src/server/ServerService.ts
index 9ae4cf4db6..8200b24fd4 100644
--- a/packages/backend/src/server/ServerService.ts
+++ b/packages/backend/src/server/ServerService.ts
@@ -176,10 +176,10 @@ export class ServerService {
 		fastify.server.on('error', err => {
 			switch ((err as any).code) {
 				case 'EACCES':
-					this.logger.error(`You do not have permission to listen on port ${this.config.port}${this.config.host ? ` of host ${this.config.host}` : ''}`);
+					this.logger.error(`You do not have permission to listen on port ${this.config.port}.`);
 					break;
 				case 'EADDRINUSE':
-					this.logger.error(`Port ${this.config.port}${this.config.host ? ` on ${this.config.host}` : ''} is already in use by another process.`);
+					this.logger.error(`Port ${this.config.port} is already in use by another process.`);
 					break;
 				default:
 					this.logger.error(err);
@@ -194,6 +194,6 @@ export class ServerService {
 			}
 		});
 
-		fastify.listen({ port: this.config.port, host: this.config.host });
+		fastify.listen({ port: this.config.port, host: '0.0.0.0' });
 	}
 }
diff --git a/packages/backend/test/utils.ts b/packages/backend/test/utils.ts
index 7539adc68c..50988939aa 100644
--- a/packages/backend/test/utils.ts
+++ b/packages/backend/test/utils.ts
@@ -19,7 +19,6 @@ const _dirname = dirname(_filename);
 
 const config = loadConfig();
 export const port = config.port;
-export const host = config.host || "localhost";
 
 export const api = async (endpoint: string, params: any, me?: any) => {
 	endpoint = endpoint.replace(/^\//, '');
@@ -29,7 +28,7 @@ export const api = async (endpoint: string, params: any, me?: any) => {
 	} : {};
 
 	try {
-		const res = await got<string>(`http://${host}:${port}/api/${endpoint}`, {
+		const res = await got<string>(`http://localhost:${port}/api/${endpoint}`, {
 			method: 'POST',
 			headers: {
 				'Content-Type': 'application/json',
@@ -67,7 +66,7 @@ export const request = async (path: string, params: any, me?: any): Promise<{ bo
 		i: me.token,
 	} : {};
 
-	const res = await fetch(`http://${host}:${port}/${path}`, {
+	const res = await fetch(`http://localhost:${port}/${path}`, {
 		method: 'POST',
 		headers: {
 			'Content-Type': 'application/json',
@@ -124,7 +123,7 @@ export const uploadFile = async (user: any, _path?: string): Promise<any> => {
 	formData.append('file', fs.createReadStream(absPath));
 	formData.append('force', 'true');
 
-	const res = await got<string>(`http://${host}:${port}/api/drive/files/create`, {
+	const res = await got<string>(`http://localhost:${port}/api/drive/files/create`, {
 		method: 'POST',
 		body: formData,
 		retry: {
@@ -161,7 +160,7 @@ export const uploadUrl = async (user: any, url: string) => {
 
 export function connectStream(user: any, channel: string, listener: (message: Record<string, any>) => any, params?: any): Promise<WebSocket> {
 	return new Promise((res, rej) => {
-		const ws = new WebSocket(`ws://${host}:${port}/streaming?i=${user.token}`);
+		const ws = new WebSocket(`ws://localhost:${port}/streaming?i=${user.token}`);
 
 		ws.on('open', () => {
 			ws.on('message', data => {
@@ -223,7 +222,7 @@ export const waitFire = async (user: any, channel: string, trgr: () => any, cond
 export const simpleGet = async (path: string, accept = '*/*'): Promise<{ status?: number, type?: string, location?: string }> => {
 	// node-fetchだと3xxを取れない
 	return await new Promise((resolve, reject) => {
-		const req = http.request(`http://${host}:${port}${path}`, {
+		const req = http.request(`http://localhost:${port}${path}`, {
 			headers: {
 				Accept: accept,
 			},