本研究提出了一個具有隨機需求和允許延遲付款的三階整合存貨模型，同時考慮前置時間的變化和缺貨情況，以找出對企業最適合的存貨政策以提高供應鏈的利潤。 在當今競爭激烈的市場中，供應鏈管理已經成為業界和學術界的公同探討的方向。在供應鏈中，供應鏈的成員必須相互合作才能帶來更多的利益。 而存貨政策是影響供應鏈績效的關鍵因素。 因此，本研究提出了一個三階整合存貨模型，該模型考慮隨機需求和允許延遲付款，同時更考慮到前置時間的變化和缺貨情況。 本研究目的是追求最大總利潤，並嘗試在馬可夫鏈隨機需求下，探討不同條件下之存貨政策。 本研究中決策者可控制提前期和支付時間以提高供應鏈的績效，且透過馬可夫理論推導，使本研究建立一個可預測條件下之供應鏈存貨模式。 This research proposes a three-echelon inventory model with stochastic demand and permissible delay in payments considering scenario of lead time difference and backorders to find out the suitable inventory policy to enhance profit of the supply chain. In today’s highly competitive market, the supply chain management has become a critical issue in both practice and academic and supply chain members have to cooperate with each other to bring more benefits. In addition, the inventory policy is a key factor to influence the performance of the supply chain. Therefore, this research develops a three-echelon inventory model with stochastic demand and permissible delay in payments considering scenario of lead time difference and backorders. Furthermore, the purpose of this research is to maximize the joint expect total profit on inventory model and considers Markov chain stochastic demand, which attempt to discuss the inventory policy under different conditions. In this research, decision makers can control the lead time and payment time to improve the performance of the supply chain, and through the Markov theory deduction, this research establishes a supply chain inventory model under predictable conditions. Finally, the results of this research could provide some managerial insights which support decision makers in real-world operation.