Abstract: The data of China Shanghai and Shenzhen A-share listed companies from 2007 to 2019 was used as samples to study the relationship between supplier concentration and bank credit, and to test the influence of the difference of marketization process on the relationship between supplier concentration and bank credit. The result indicates that there is a nonlinear inverted U-shaped relationship between supplier concentration and bank credit, as the level of supplier concentration increases, the bank credit acquired by enterprises shows a trend of first increa-sing and then decreasing. Compared to regions with high marketization, the relationship between supplier concentration and bank credit is more sensitive in the regions with low marketization.