Inventory management is to improve economic benefit of project procurement management by means of dominating order cycle and order quantity to minimize the stocks and total cost under the circumstance of normal construction.Firstly,inventory management involves material order,and contractors need to calculate parameters such as order cycle,order fee,order quantity,stocks fee,order lead time and safe stocks in order to make the total inventory fee minimized during construction.This article applies one branch of operations research--"inventory" to optimize the inventory management.