From the perspective of the lifecycle, the article makes a comprehensively study on network business model by stages. By analyzing the phases of development of two famous network enterprises it summarizes the business model during the lifecycle of the technologyoriented and businessoriented network enterprises. The study shows that the characteristics of the network economy are the basis on which enterprises choose business models. In the different stages of development it shows the business models of enterprises change with the different characteristics of the network economy. The network enterprises, whose business models are compatible with economic characteristics, can achieve longterm sustainable development. Finally the article makes some proposals for the network enterprises on service and charge model, product positioning, competitive strategy and other aspects.