In this paper, we set the relationship quality as the variable between the knowledge power of enterprise and governance performance of the network. Based on the Chinese R&D alliance, we analyze and explore the intermediary role of relationship quality. The result shows that relationship quality acts the strong intermediary role between three types of knowledge power (expert power, reward power and coercive power) and network governance performance. We prove that the governance on the technical innovation network is based on using the knowledge power to govern the relationship between enterprises.