diff --git a/packages/backend/src/core/FileInfoService.ts b/packages/backend/src/core/FileInfoService.ts
index e145f6699c..e6bd08ee4d 100644
--- a/packages/backend/src/core/FileInfoService.ts
+++ b/packages/backend/src/core/FileInfoService.ts
@@ -56,7 +56,8 @@ export class FileInfoService {
 		private aiService: AiService,
 		private loggerService: LoggerService,
 	) {
-		this.logger = this.loggerService.getLogger('file-info');
+		// eslint-disable-next-line @typescript-eslint/no-unnecessary-condition
+		this.logger = this.loggerService?.getLogger('file-info'); // なぜか TypeError: Cannot read properties of undefined (reading 'getLogger') と言われる
 	}
 
 	/**