Abstract: In order to explore the impact of supplier concentration on the dynamic transformation of the interactive relationship between trade credit financing and bank credit, taking A-share listed companies from 2007 to 2016 as samples, the inverted u-shaped relationship between trade credit financing and supplier concentration and the inverted u-shaped relationship between bank credit and supplier concentration were studied and revealed, the difference of its inflection point was analyzed. The results show that with the increase of supplier concentration, the interactive relationship between trade credit financing and bank credit changes from complementarity to substitution to complementarity. This study enriches the content of dynamic transformation of the interactive relationship between trade credit financing and bank credit, and provides valuable references for enterprises to timely adjust financing methods.