Based on a twolevel supply chain with reordering opportunities under advertising dependent random demand, this paper compared the supply chain members’ optimal policies between centralized and decentralized decision-making systems. The comparsion shows that it is very difficult for a single advertising subsidy mechanism to realize perfect coordination of the decentralized supply chain. Therefore, through the combined incentive mechanism which consists of trade credit and advertising subsidy, the manufacturer could induce the retailer to choose the optimal ordering quantity and advertising investment for the centralized system, and further achieve the Pareto improvement of the manufacturer’s and retailer’s expected profits. Finally, this paper proposed a numerical example to verify the main conclusions, and to illustrate the effect of adjusting the relevant parameter on optimal policies and the splitting of expected profits of supply chain.