Based on the differences in managerial ability during the establishment of the internal control system of listed companies, this paper selects the A-share listed companies in 2012-2017 as a research sample, studies the relationship between internal control and financing constraints, and the impact of managerial ability. The study found that the higher the quality of internal control, the lower the degree of corporate financing constraints; the managerial ability has a regulatory effect on the relationship between the company"s internal control and financing constraints, that is, companies with higher management capabilities, internal control can more ease financing The degree of constraint. At the same time, in the listed companies with higher management capabilities, compared with the state-owned listed companies, the internal control of non-state-owned listed companies has a relatively significant mitigation effect on financing constraints.