diff --git a/packages/backend/src/queue/processors/InboxProcessorService.ts b/packages/backend/src/queue/processors/InboxProcessorService.ts
index bf36fe4373..1257467cfe 100644
--- a/packages/backend/src/queue/processors/InboxProcessorService.ts
+++ b/packages/backend/src/queue/processors/InboxProcessorService.ts
@@ -31,6 +31,7 @@ import { SkApInboxLog } from '@/models/_.js';
 import type { Config } from '@/config.js';
 import { ApLogService, calculateDurationSince } from '@/core/ApLogService.js';
 import { UpdateInstanceQueue } from '@/core/UpdateInstanceQueue.js';
+import { isRetryableError } from '@/misc/is-retryable-error.js';
 import { QueueLoggerService } from '../QueueLoggerService.js';
 import type { InboxJobData } from '../types.js';
 
@@ -312,6 +313,14 @@ export class InboxProcessorService implements OnApplicationShutdown {
 				}
 			}
 
+			if (!isRetryableError(e)) {
+				if (e instanceof Error) {
+					return `skip: permanent error ${e.name}: ${e.message}`;
+				} else {
+					return `skip: permanent error ${e}`;
+				}
+			}
+
 			throw e;
 		}
 		return 'ok';