To the problems of water flow turbulence,cross-flow,backflow intensity exceeding the standard in the entrance area after the upgrade and renovation of the Yantan ship lift.This paper uses a two-dimensional mathematical model to focus on the influence of different arrangements of diversion piers on the navigational flow conditions in the entrance area,and analyzes the flow pattern under different shapes,number and relative spacing of diversion piers.By comparing the hydraulic parameters such as transverse flow velocity,longitudinal flow velocity and backflow velocity,the layout law of diversion pier is further explored and the layout mode of diversion pier is optimized.The results show that diversion piers have obvious improvement effect on the navigational flow conditions in the entrance area.The recommended arrangement is 7-8 octagonal diversion piers in the entrance area downstream of the Yantan ship lift,with a spacing-to-length ratio between 0.50 and 1.00.This arrangement effectively improves the navigational flow conditions in the entrance area downstream of the ship lift,meeting the requirements for navigation.