Based on the panel data of 17 Commercial Banks in China from 2013 to 2019, the relationship between Internet finance, interest rate marketization and the profitability of commercial banks is studied empirically using fixed effects and mediating effects models, etc. The results show that Internet finance has a suppressive effect on the profitability of commercial banks. There is a U‐shaped relationship between interest rate marketization and The profitability of commercial banks, i.e. as the Interest Rate marketization advances, the profitability of commercial banks shows a trend of "falling first and then rising"; On the whole, there is a partial intermediary effect between Internet finance and the profitability of commercial banks, i.e. some of the effects of Internet finance can affect the profitability of commercial banks through interest rate marketization.