<p>Interregional technology transfer is a vital source of external knowledge acquisition for regions and is crucial for enhancing regional innovation capabilities. However, the factors influencing interregional technology transfer have not been systematically analysed. Based on the data of 316,960 patent transactions in China from 2001 to 2020, this paper constructs an interregional technology transfer network covering 295 cities in China and reveals the spatio-temporal evolution characteristics of this network from both spatial and level aspects. Simultaneously, we propose an analytical framework including distance–proximity factor and empirically demonstrate the impact of both distance and proximity factors on interregional technology transfer using data on patent transactions between cities. The results of social network analysis show that China's interregional technology transfer network gradually develops from a sparse network to a dense network. There are significant differences in the levels of cities within the network, with developed cities such as Beijing, Shenzhen and Guangzhou being the core cities of the network and the core–periphery structure being obvious. The empirical results indicate that geographical distance, cultural distance and administrative distance have significant inhibitory effects on interregional technology transfer. On the contrary, transportation proximity, informational proximity and institutional proximity are capable of promoting interregional technology transfer and moderate the negative effect of the distance factors. Our study confirms the influencing factors of interregional technology transfer and provides a reference for policymakers to design more effective interregional technology transfer policies.</p>