Platform is a globalization business model，and its related economy also becomes one remarkable economic phenomenon． Hybrid e-commerce platforms，such as JD and Amazon，serve as intermediaries providing marketplace for third-party sellers and buyers，and resellers selling competing products to consumers．The paper tries to investigate the following questions through pyramid spatial model． Why does some products have a lot of third-party sellers，while others have fewer? Are platforms with more third-party sellers better than a hybrid e-commerce platform? Why does the price of online direct sale lie among the prices of third-party sellers? Which，online direct sales or third-party services，is dominant in the total profit of hybrid e-commerce platforms? Our analysis indicates that product features，such as product costs，transaction costs，market size，and so on，lead to the different numbers of third-party sellers． Each hybrid e-commerce platform should control the number of third-party sellers: neither too much nor too little． A moderate price of online direct sales increases sales，and improves prices． Online direct sales dominate the total profit of platforms when there are fewer third-party sellers，while third-party services dominate the profit when there are many third-party sellers．Additionally，the basic model is also extended to two-sided platforms． It is concluded that JD model is better than Tmall model，and that Tmall Model is better than both Taobao model and Meituan model，given fixed N，r and f． As for two-sided platforms，two-party tariff pricing model is better than membership fee and usage fee pricing model．