There is obvious imbalance in the distribution of scientific and technological innovation resources in China. Accelerating the construction of regional scientific and technological innovation network is an important way to promote the flow and sharing of scientific and technological innovation resources, the effective transformation of scientific and technological achievements, and the narrowing of regional innovation gap. Build China's regional scientific and technological innovation network from the perspective of patent transfer, use the relevant data of 31 provinces from 1990 to 2020, and divide the research period from 1990 to 2000, from 2001 to 2010, and from 2011 to 2020, use social network analysis and chord diagram to reveal its space-time evolution characteristics, and use negative binomial regression model to explore its evolution proximity mechanism, so as to promote the flow and sharing of regional innovation resources, cooperation and mutual benefit of innovation entities, provide theoretical basis and reference for the effective transformation of innovation achievements and regional coordinated development. The results show that: (1) China's regional scientific and technological innovation network has evolved into a complex network, and the network connectivity compatibility and heterogeneity coexist; (2) The network accessibility and technology transfer efficiency have been significantly improved, and the characteristics of the small world are obvious; (3) The spatial distribution of the network is unbalanced and the gradient difference is obvious; (4) The "core- edge" pattern is constantly strengthened, and path dependence and path creation coexist; (5) Geographical proximity and economic proximity significantly promote the evolution of regional scientific and technological innovation networks, while technological proximity, cognitive proximity and industrial proximity significantly inhibit the evolution of regional scientific and technological innovation networks. Finally, it puts forward countermeasures and suggestions to promote the development of China's scientific and technological innovation network, such as improving the patent trading mechanism, promoting the evolution of the scientific and technological innovation network to a multi-center and multi-level structure, and giving full play to the role of intermediary provinces as "bridges".