In the e-commerce era, an e-tailer sells a single product to consumers in two ways: either through the traditional direct selling, or through the rebate selling with the participating of a third party rebate store. The optimal pricing strategy for the e-tailer and rebate strategy for the third party rebate store is studied using the consumer utility theory. The results show that, whether the e-tailer introduces a rebate channel is dependent on the fill rate of rebate product, the extra cost that consumers buy the rebate product, and the rebate redemption. Comparing with the centralized system, the optimal retail price in the decentralized case will decrease, while the rebate store will reduce the rebate value to consumers. As a consequence, it aggravates the channel conflicts and system inefficiency. Furthermore, a revised revenue sharing contract is designed to coordinate the system, which can maximize the system profits and achieve a win-win situation for both partners. Finally, numerical examples are used to verify the effectiveness of the contract.