Abstract: Due to the price fluctuation of the raw materials, supply chain firms need to relieve the risks of the profit decrease through the procurement price flexibility mechanism. In this paper, a supply chain consist of a supplier and a manufacturer is considered, where the manufacturer buys the raw material from the supplier at the beginning of the lead time and the supplier delivers the raw material to the manufacturer at some time later. By designing a procurement price flexibility contract, the risk relief of the contract on the supplier and the manufacture's profit is analyzed. Using the Stackelberg game, mathematic models are developed to analyze the optimal procurement quantity of the manufacturer and the optimal contract parameters of the supplier. Also the optimal results change trend with the change of the price flexibility contract parameters is discussed. Using variance of the profit the risk undertaken by the supplier and the manufacturer respectively is and measured the change of the risk with the change of the price flexibility parameters is analyzed. The results show that supply contract with proper parameters can improve the profit and relief the profit risk of the supplier and the manufacturer respectively.

Key words: supply chain management, procurement price flexibility contract, stackelberg game, risk-sharing