The flow of innovation factors is important for improving the mismatch of innovation factors and optimizing the spatial allocation of innovation in cities. Using patent filing and transfer data，this paper analyzes the innovation pattern，process，and evolution mechanism in the Yangtze River Delta region through network analysis and spatial analysis，and finds that：there is a hierarchy in the patent transfer network in the Yangtze River Delta region；external dependence of patents declines in these cities，there is a strong head preference and spatial heterogeneity in the flow of innovation factors，and the adsorption and spillover capacity of innovation factors is increasingly concentrated in the head cities；city size and changes in the structure of patent supply and demand play an important role in the flow network of patents，and multidimensional proximity，such as geographical distance，administrative division，and cultural differences，are also important factors affecting the flow of innovation factors；Finally，the paper puts forward relevant policy recommendations based on the spatial pattern and evolution mechanism of the patent flow network in the Yangtze River Delta region.