Abstract: Inventory decision of the omni-channel retailer under BOPS strategy is researched to improve both retailers' operation efficiency and customers' shopping experience. Traditional dual channel and omni-channel under BOPS strategy's inventory decision models are built respectively based on the Newsvendor model, and a comparative analysis of the impact of BOPS strategy on store optimal inventory decisions and retailers' profit is made. The research results show that customer choice behaviors have different effects between omni-channel and dual channel operations. Mainly three conclusions are drawn. 1) The optimal order quantity of store under dual channel increases with the increasing of customers' expectation in store inventory level, and the characteristics of the omni-channel are opposite to those of the dual channel; 2) When the BOPS replenishment waiting cost is low, the total demand of omni-channel store under BOPS strategy is greater than that of dual channel; 3) When customers expect lower store inventory, omni-channel retailers have lower profit than that of dual channel.