The upgrading of export product structure is essential for China to become a trade power. The influence of bank?enterprise geographical proximity on the upgrading of export product structure and its micro?mechanisms have been explored， based on the data from Chinese Industrial Enterprise Database， Chinese Customs Import and Export Database， Financial License Information System of National Financial Regulatory Administration， and United Nations' Statistics of Goods and Trade. The study finds that bank?enterprise geographical proximity can promote the upgrading of export product structure， and this conclusion still holds after a series of robustness tests. Alleviating information asymmetry and financing constraints are the micro mechanisms by which bank?enterprise geographic proximity plays its role， whose effect is stronger in non?central cities， county areas， private enterprises and SMEs than in cities with more developed fintech. This study provides empirical evidence for the rationality of bank branch sinking， and suggests that the government should continue to optimize the layout of bank branches according to the geographical distribution of SMEs， and promote the development of fintech.