Taking the panel data obtained from the micro and macro matching of China's A-share listed companies in 30 provinces and cities from 2010 to 2019 as samples, this paper constructs A two-way fixed effect model and a panel simultaneous equation model to demonstrate the influence path of two-way fiscal imbalance on corporate tax avoidance. The research shows that there is a high two-way imbalance in our country, the fiscal vertical imbalance is positive to promote corporate tax avoidance, and the fiscal horizontal imbalance is negative to inhibit corporate tax avoidance. From the perspective of transmission path, the vertical fiscal imbalance promotes corporate tax avoidance by reducing the intensity of local tax collection and administration and government subsidies, while the horizontal fiscal imbalance inhibits corporate tax avoidance by increasing the enthusiasm of local tax collection and administration and government subsidies. From the perspective of regional differentiation, the eastern region has the same conclusion as the whole sample, but in the non-eastern region, the vertical and horizontal fiscal imbalances are negatively correlated with corporate tax avoidance, mainly because enterprises in the central and western regions can obtain more government subsidies by reducing tax avoidance. From the perspective of local government debt scale differentiation, the effects of vertical and horizontal fiscal imbalance on corporate tax avoidance are established in regions with low debt scale. From the perspective of cash flow differentiation, the relationship between vertical imbalance and corporate tax avoidance is established in the group with low cash flow, while the relationship between horizontal imbalance and corporate tax avoidance is established in the group with high cash flow.