Ship-type standardization is an effective way to improve the traffic capacity of the Three Gorges ship lock.This paper studies the quantitative effect of standard ship rate on traffic capacity of ship lock.The paper sets up a simulation model to study the traffic capacity in different standard ship rates based on the process of ships passing through the Three Gorges ship lock.The simulation results show that the simulation model can well simulate the process of ships passing through the Three Gorges ship lock,and the benefit of standard ships in prompting the efficiency of the ship lock will multiply when the standard ship rate is more than 90%.Compared with the traffic capacity of the ship lock,the increase of the standard ship rate can improve the quality of ship service remarkably.