diff --git a/core/api_coupon.go b/core/api_coupon.go
index 9a7e396..8e788f6 100644
--- a/core/api_coupon.go
+++ b/core/api_coupon.go
@@ -231,7 +231,7 @@ func queryCoupon(mongoClient gocommon.MongoClient, w http.ResponseWriter, r *htt
 	var coupon couponDoc
 	if err := mongoClient.FindOneAs(CollectionCoupon, bson.M{
 		"_id": roundObj,
-	}, &coupon, options.FindOne().SetProjection(bson.M{"_id": 0, "effect": 1, "name": 1, "reason": 1, "total": 1, "remains": 0, "used": 0})); err != nil {
+	}, &coupon, options.FindOne().SetProjection(bson.M{"effect": 1, "name": 1, "reason": 1, "total": 1, "desc": 1}).SetReturnKey(false)); err != nil {
 		logger.Println("[queryCoupon] FindOneAs failed :", err)
 		w.WriteHeader(http.StatusInternalServerError)
 		return