diff --git a/src/modules/reminder/index.ts b/src/modules/reminder/index.ts
index cc02141..c0a3f36 100644
--- a/src/modules/reminder/index.ts
+++ b/src/modules/reminder/index.ts
@@ -115,12 +115,16 @@ export default class extends Module {
 
 		const done = msg.includes(['done', 'やった', 'やりました', 'はい']);
 		const cancel = msg.includes(['やめる', 'やめた', 'キャンセル']);
+		const isOneself = msg.userId === remind.userId;
 
-		if (done || cancel) {
+		if ((done || cancel) && isOneself) {
 			this.unsubscribeReply(key);
 			this.reminds.remove(remind);
 			msg.reply(done ? getSerif(serifs.reminder.done(msg.friend.name)) : serifs.reminder.cancel);
 			return;
+		} else if (isOneself === false) {
+			msg.reply("イタズラはめっですよ！");
+			return;
 		} else {
 			if (msg.isDm) this.unsubscribeReply(key);
 			return false;