diff --git a/src/services/note/delete.ts b/src/services/note/delete.ts
index 2b99b4b85e..4b0f482c08 100644
--- a/src/services/note/delete.ts
+++ b/src/services/note/delete.ts
@@ -8,6 +8,8 @@ import Following from '../../models/following';
 import renderTombstone from '../../remote/activitypub/renderer/tombstone';
 import { updateNoteStats } from '../update-chart';
 import config from '../../config';
+import NoteUnread from '../../models/note-unread';
+import read from './read';
 
 /**
  * 投稿を削除します。
@@ -36,6 +38,15 @@ export default async function(user: IUser, note: INote) {
 		deletedAt: deletedAt
 	});
 
+	// この投稿が関わる未読通知を削除
+	NoteUnread.find({
+		noteId: note._id
+	}).then(unreads => {
+		unreads.forEach(unread => {
+			read(unread.userId, unread.noteId);
+		});
+	});
+
 	//#region ローカルの投稿なら削除アクティビティを配送
 	if (isLocalUser(user)) {
 		const content = pack(renderDelete(renderTombstone(`${config.url}/notes/${note._id}`), user));