近年來，通路的型態已越趨成熟且多樣化，供需之間的通路協調與競爭亦衍生出許多方式，包含商品折扣、價格競爭、低價策略等，因此，企業在滿足供需的同時，也重視價格議定的討論，常見以商品折扣為策略，紛紛提出不同的商品折扣方案，讓需求者有更多樣的選擇。
　　本研究主要探討的主題為考量在多通路競爭的環境下，單一製造商以數量折扣和現金折扣作為商品折扣的策略，一個零售商所獲得的批發價格是以數量折扣為依據，另一個零售商所獲得的批發價格則是以現金折扣為依據，其兩零售商彼此定價與訂購量的關係。
　　在折扣策略中，數量折扣分為累計和一次性的折扣方式，而現金折扣分為在折扣期間內繳費優惠、非折扣期間繳費和延遲繳費，本研究的競爭模型分別為「累計數量折扣v.s.在折扣期間內繳費優惠的現金折扣」和「一次性數量折扣v.s.在折扣期間內繳費優惠的現金折扣」為建構，並利用總體利潤最高的交叉彈性係數為基礎，找出折扣策略中利潤、售價與訂購量之關係。
　　本研究的結果可顯示出商品折扣率的增加，會使售價降低、訂購量增加、利潤會有不同的波動幅度，所以在面對不同折扣率的環境，企業必須在公布價格前先議定好可承受的折扣方案，才能獲取最大利潤時，亦提供給消費者不同的選擇。

Recently, channels’ type has become more mature and various. Channel members coordinate or compete with each other in many ways such as product discount, price competition, and low-price strategy, therefore, when enterprises try to meet the demand, they also take price-negotiation seriously. Product discount is a normal strategy for enterprises to provide differently. In that way, they can let customers have more choices.
The main topic of this research is considering the relationship of pricing and order quantity between two retailers. Two retailers are under dual-channel with competition. The channel is divided two parts by a manufacturer with strategies of quantity discount and cash discount and two retailers. One of retailer decides its wholesale price by quantity discount and the other decides its wholesale price by cash discount. Quantity discount has two ways in discount. One is cumulative quantity discount, and another one is single quantity discount. Cash discount is distinguished by pay and get discount within period, pay during no discount period, and payment delay. Models of this research are “cumulative quantity discount v.s. pay and get discount within period” and “single quantity discount v.s. pay and get discount within period.” Using the intersection coefficient of elasticity, the channel’s total profit can be higher. We have found the relationship among profit, price and quantity under discount strategy in this research.
Our result shows that the more product discount, the lower price, the higher order quantity, and the different profit will be. We can conclude that when facing various discount rates, enterprises need to measure affordable discount plan before giving consumers to choose, and then they can maximize their profit in the end.

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