diff --git a/packages/backend/migration/1756824506000-optimize-drive-files-query.js b/packages/backend/migration/1756824506000-optimize-drive-files-query.js
new file mode 100644
index 0000000000..0716b321fc
--- /dev/null
+++ b/packages/backend/migration/1756824506000-optimize-drive-files-query.js
@@ -0,0 +1,19 @@
+/*
+ * SPDX-FileCopyrightText: syuilo and misskey-project
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+export class OptimizeDriveFilesQuery1756824506000 {
+	name = 'OptimizeDriveFilesQuery1756824506000'
+
+	async up(queryRunner) {
+		// Create optimized partial index for drive files query performance
+		// This index is specifically designed for the common query pattern:
+		// SELECT * FROM drive_file WHERE userId = ? AND folderId IS NULL ORDER BY id DESC
+		await queryRunner.query(`CREATE INDEX "IDX_drive_file_userid_null_folderid_id_desc" ON "drive_file" ("userId", ("folderId" IS NULL), "id" DESC)`);
+	}
+
+	async down(queryRunner) {
+		await queryRunner.query(`DROP INDEX "IDX_drive_file_userid_null_folderid_id_desc"`);
+	}
+}
diff --git a/packages/backend/src/models/DriveFile.ts b/packages/backend/src/models/DriveFile.ts
index 7b03e3e494..2bb672ea1c 100644
--- a/packages/backend/src/models/DriveFile.ts
+++ b/packages/backend/src/models/DriveFile.ts
@@ -10,6 +10,7 @@ import { MiDriveFolder } from './DriveFolder.js';
 
 @Entity('drive_file')
 @Index(['userId', 'folderId', 'id'])
+@Index('IDX_drive_file_userid_null_folderid_id_desc', { synchronize: false })
 export class MiDriveFile {
 	@PrimaryColumn(id())
 	public id: string;