diff --git a/.config/example.yml b/.config/example.yml
index 59201fce0a..e787274fdc 100644
--- a/.config/example.yml
+++ b/.config/example.yml
@@ -58,8 +58,7 @@ drive:
 
   # OR
 
-  # storage: 'object-storage'
-  # service: 'minio'
+  # storage: 'minio'
   # bucket:
   # prefix:
   # config:
diff --git a/src/config/types.ts b/src/config/types.ts
index b2e28f7306..b554650820 100644
--- a/src/config/types.ts
+++ b/src/config/types.ts
@@ -51,9 +51,8 @@ export type Source = {
 
 	drive?: {
 		storage: string;
-		bucket: string;
-		prefix: string;
-		service?: string;
+		bucket?: string;
+		prefix?: string;
 		config?: any;
 	};
 
diff --git a/src/services/drive/add-file.ts b/src/services/drive/add-file.ts
index 4d14325db2..91bf5b010c 100644
--- a/src/services/drive/add-file.ts
+++ b/src/services/drive/add-file.ts
@@ -21,36 +21,31 @@ import config from '../../config';
 const log = debug('misskey:drive:add-file');
 
 async function save(readable: stream.Readable, name: string, type: string, hash: string, size: number, metadata: any): Promise<IDriveFile> {
-	if (config.drive && config.drive.storage == 'object-storage') {
-		if (config.drive.service == 'minio') {
+	if (config.drive && config.drive.storage == 'minio') {
+		const minio = new Minio.Client(config.drive.config);
+		const id = uuid.v4();
+		const obj = `${config.drive.prefix}/${id}`;
+		await minio.putObject(config.drive.bucket, obj, readable);
 
-			const minio = new Minio.Client(config.drive.config);
-			const id = uuid.v4();
-			const obj = `${config.drive.prefix}/${id}`;
-			await minio.putObject(config.drive.bucket, obj, readable);
+		Object.assign(metadata, {
+			withoutChunks: true,
+			storage: 'minio',
+			storageProps: {
+				id: id
+			},
+			url: `${ config.drive.config.secure ? 'https' : 'http' }://${ config.drive.config.endPoint }${ config.drive.config.port ? ':' + config.drive.config.port : '' }/${ config.drive.bucket }/${ obj }`
+		});
 
-			Object.assign(metadata, {
-				withoutChunks: true,
-				storage: 'object-storage',
-				storageProps: {
-					id: id
-				},
-				url: `${ config.drive.config.secure ? 'https' : 'http' }://${ config.drive.config.endPoint }${ config.drive.config.port ? ':' + config.drive.config.port : '' }/${ config.drive.bucket }/${ obj }`
-			});
+		const file = await DriveFile.insert({
+			length: size,
+			uploadDate: new Date(),
+			md5: hash,
+			filename: name,
+			metadata: metadata,
+			contentType: type
+		});
 
-			const file = await DriveFile.insert({
-				length: size,
-				uploadDate: new Date(),
-				md5: hash,
-				filename: name,
-				metadata: metadata,
-				contentType: type
-			});
-
-			return file;
-		} else {
-			throw 'unknown storage type';
-		}
+		return file;
 	} else {
 		// Get MongoDB GridFS bucket
 		const bucket = await getDriveFileBucket();
diff --git a/src/services/drive/delete-file.ts b/src/services/drive/delete-file.ts
index bf9c80f485..5494023f46 100644
--- a/src/services/drive/delete-file.ts
+++ b/src/services/drive/delete-file.ts
@@ -4,37 +4,35 @@ import DriveFileThumbnail, { DriveFileThumbnailChunk } from '../../models/drive-
 import config from '../../config';
 
 export default async function(file: IDriveFile, isExpired = false) {
-	if (file.metadata.withoutChunks) {
-		if (file.metadata.storage == 'object-storage') {
-			const minio = new Minio.Client(config.drive.config);
-			const obj = `${config.drive.prefix}/${file.metadata.storageProps.id}`;
-			await minio.removeObject(config.drive.bucket, obj);
-		}
-	} else {
-		// チャンクをすべて削除
-		await DriveFileChunk.remove({
-			files_id: file._id
-		});
-
-		await DriveFile.update({ _id: file._id }, {
-			$set: {
-				'metadata.deletedAt': new Date(),
-				'metadata.isExpired': isExpired
-			}
-		});
-
-		//#region サムネイルもあれば削除
-		const thumbnail = await DriveFileThumbnail.findOne({
-			'metadata.originalId': file._id
-		});
-
-		if (thumbnail) {
-			await DriveFileThumbnailChunk.remove({
-				files_id: thumbnail._id
-			});
-
-			await DriveFileThumbnail.remove({ _id: thumbnail._id });
-		}
-		//#endregion
+	if (file.metadata.storage == 'minio') {
+		const minio = new Minio.Client(config.drive.config);
+		const obj = `${config.drive.prefix}/${file.metadata.storageProps.id}`;
+		await minio.removeObject(config.drive.bucket, obj);
 	}
+
+	// チャンクをすべて削除
+	await DriveFileChunk.remove({
+		files_id: file._id
+	});
+
+	await DriveFile.update({ _id: file._id }, {
+		$set: {
+			'metadata.deletedAt': new Date(),
+			'metadata.isExpired': isExpired
+		}
+	});
+
+	//#region サムネイルもあれば削除
+	const thumbnail = await DriveFileThumbnail.findOne({
+		'metadata.originalId': file._id
+	});
+
+	if (thumbnail) {
+		await DriveFileThumbnailChunk.remove({
+			files_id: thumbnail._id
+		});
+
+		await DriveFileThumbnail.remove({ _id: thumbnail._id });
+	}
+	//#endregion
 }