Abstract: The rise and prosperity of e-commerce, breaking the traditional business model, which provides lower operation cost for enterprises and more convenient means of purchase for consumers, makes enterprises, e-commerce platform and logistics enterprises to form E-supply chain system. According to the current profit model of e-commerce platform in E-supply chain system, the third party, e-commerce platform is incorporated into system decision. Considering the difference of dominant patterns and the role of commission in E-supply chain system, the dominant models and coordination mechanism of E-supply chain based on e-commerce platform which is fully taken into account in decision process are studied in this paper.
First, two decentralized decision-making models of E-supply chain, including manufacturer's dominant model and e-commerce platform's dominant model, and centralized decision-making model are constructed. Then, for each model, the corresponding optimal decisions is solved. And the comparative analysis of the optimal decisions is carried out. On this basis, commission coordination mechanism is designed to achieve coordination for each dominant model. Finally, conclusions are demonstrated with numerical examples. The results indicate that:(1) In the decentralized decision-making models, the dominance of E-supply chain contributes positively to the increase of dominant enterprise's profit. When manufacturer dominating system, the selling price, the service level of e-commerce platform, and the profits of manufacturer and E-supply chain system are higher, so do they increase with the increase of the commission rate. Nevertheless, the profit of the manufacturer decreases as commission rate increases. (2) In the centralized decision-making model, the selling price, the service level of the e-commerce platform and the profit of E-supply chain system are highest, besides, they are not affected by commission rate.
The commission rate has nothing to do with system's revenue under the centralized decision-making model, but in the decentralized decision-making models, the profits of manufacturer and e-commerce platform changes in the opposite direction with the commission rate changes. Therefore, the article embraces commission rate as a coordination tool, and designs commission coordination mechanism to achieve the coordination of the system by resizing commission rate. In commission coordination mechanism, if ρ satisfies

the commission coordination mechanism can achieve system coordination.
The research results will further enrich and perfect the theoretical basis of E-supply chain, and provide reference guides for enterprises to make decisions. However, only E-supply chain structure of a single manufacturer and a single electrical platform are constructed as the research object. In future work, the "many-to-one" E-supply chain should be taken into consideration.

Key words: e-commerce platform, E-supply chain, commission coordination mechanism