Abstract: This paper explores how pharmaceutical firms build their R&D network in order to improve the performance of product innovation under different strategic orientation. A longitude case study of a pharmaceutical firm is conducted. The impact of R&D network characteristics on product innovation performance and the influence of strategic orientation on R&D network characteristics are presented. First of all, our results indicate that three characteristics of R&D network exert a positive effect on product innovation performance. The product innovation performance of the focus enterprise reaches the maximum when the R&D network is of large scale, high openness and high heterogeneity of network resources. Secondly, two types of strategic orientation have positive but different effect on the characteristics of R&D network. Specifically, the market orientation only exert a less positive impact on the scale of R&D network, however, entrepreneurial orientation has positive effect on the three characteristics of R&D network to a great extent. Moreover, the single market orientation has less influence on product innovation performance of enterprises, the product innovation performance of enterprises is more better when the high market orientation and high entrepreneurial orientation have integrated together and form a combination of strategic orientation.