diff --git a/packages/backend/src/misc/is-user-related.ts b/packages/backend/src/misc/is-user-related.ts
index 93c9b2b814..1604fd0419 100644
--- a/packages/backend/src/misc/is-user-related.ts
+++ b/packages/backend/src/misc/is-user-related.ts
@@ -8,6 +8,10 @@ export function isUserRelated(note: any, userIds: Set<string>, ignoreAuthor = fa
 		return true;
 	}
 
+	if (note.mentions != null && note.mentions.filter(userId => userId !== note.userId && userIds.has(userId)).length > 0) {
+		return true;
+	}
+
 	if (note.reply != null && note.reply.userId !== note.userId && userIds.has(note.reply.userId)) {
 		return true;
 	}