Under the background of China’s transitional economy and unique system, this paper takes the data of A-share listed companies in Shenzhen and Shanghai stock exchanges from 2009 to 2019 as samples to conduct an empirical study on the relationship between CEO tenure and corporate financing constraints, and finds that CEO tenure length has a negative effect on corporate financing constraints. Further grouping the samples according to the nature of equity, product market competition and CEO age, the research finds that the negative effect of CEO tenure on corporate financing constraints is more significant in the sample group of non-state-owned enterprises, stronger product market competition and older CEOs. The research results are helpful for enterprises to reasonably allocate and play CEO functions according to different situations, and also provide empirical basis for government departments and financial institutions to formulate and improve relevant policies to alleviate the financing difficulties of enterprises.