The impact of the knowledge diversity of coopeting partners on innovation performance, and the moderating role of the knowledge management——the establishment of R&D centers, the degree of market localization, intellectual property right management, are studied in this research. The results show that the knowledge diversity of a firm’s coopeting partners significantly promotes its innovation performance. The moderating effects of the knowledge management are as follows: First of all, intellectual property right management has a positive moderating effect on the relationship between the knowledge diversity of coopeting partners and innovation performance; Secondly, the degree of market localization has a negative moderating effect on the relationship between the knowledge diversity of coopeting partners and innovation performance. Thirdly, although the establishment of R&D centers can effectively improve the firms’ innovation performance, the establishment of R&D centers and the number of R&D centers have no significant moderating effect on the relationship between the knowledge diversity of coopeting partners and innovation performance.