The rapid development of digital finance has had a huge impact on economic growth.This paper summarizes and sorts out,by using panel data of 210 important cities across the country,the impact mechanism of digital finance on economic growth:promoting loan business and resident consumption,enriching the business system of the financial industry,improving the allocation efficiency of financial resources and reducing transaction costs.The results show that digital finance does have a significant impact on economic growth,and that economic growth will increase by 0.26%for every 1%increase in digital finance.Based on this,some meaningful and constructional countermeasures and suggestions are puts forward.