diff --git a/modules/shop/api_buy.go b/modules/shop/api_buy.go
index 776ee00e3..284c890d7 100644
--- a/modules/shop/api_buy.go
+++ b/modules/shop/api_buy.go
@@ -55,7 +55,7 @@ func (this *apiComp) Buy(session comm.IUserSession, req *pb.ShopBuyReq) (code pb
 		}
 	}
 
-	if code = this.module.ConsumeRes(session, conf.Need, true); code != pb.ErrorCode_Success {
+	if code = this.module.ConsumeRes(session, need, true); code != pb.ErrorCode_Success {
 		return
 	}
 	if code = this.module.DispenseRes(session, conf.Iteminfo, true); code != pb.ErrorCode_Success {