diff --git a/src/rooms/commands/ChangeCardCommand.ts b/src/rooms/commands/ChangeCardCommand.ts
index d8f895c..cde6ac2 100644
--- a/src/rooms/commands/ChangeCardCommand.ts
+++ b/src/rooms/commands/ChangeCardCommand.ts
@@ -29,7 +29,7 @@ export class ChangeCardCommand extends Command<CardGameState, { client: Client,
             client.send('change_card_s2c', {errcode: 2, errmsg: '当前玩家已换卡'});
             return;
         }
-        const maxCount = singleton(GameEnv).roundDrawNum;
+        const maxCount = singleton(GameEnv).cardChangeNum;
         if (cards.length > maxCount) {
             client.send('change_card_s2c', {errcode: 3, errmsg: '换卡数量超过限制'});
             return;