The overall fixed-bed model is established to study navigation condition of downstream approach channel and entrance area of Wacun hydro-junction to get good flow condition for navigation.According to the model test result:affected by water diffusion from power station tail and free jet from right bank slope of tail water outlet,the flow condition in downstream approach channel and entrance area with poorer flow regime and excessive amounts of longitudinal velocity and lateral velocity do not meet the requirements for ship safety navigation.This paper discusses the influence of engineering measures on water flow conditions,such as extending the length of the navigation wall,expanding the slope of the right bank,and adding the other piers.The recommended scheme determined by the comparison and optimization of model schemes solved the problem of larger cross flow in the entrance area well.The navigation flow conditions of downstream approach channel and entrance area meet the requirements of safe navigation for the ship.