In view of the increasing demand of ship passing through dam and the insufficiency of ship lock passing capacity,this paper studies the optimization of ships bearing off Gezhouba ship lock,and puts forward two modes which are called “full-synchronously bear off lock” and “semi-synchronously bear off lock”.Based on the analysis of the current situation of ships bearing off Gezhouba ship lock,and the layout of navigation construction facilities and channel conditions,the basic operation organization scheme for ships “synchronously bearing off” Gezhouba ship lock is obtained.The mathematical models of “full-synchronously bearing off lock”,“semi-synchronously bearing off lock” and “one by one bearing off lock” are established,and it is calculated that the time of bearing off Gezhouba ship lock can be shortened by selecting appropriate scheme to carry out synchronous bearing off.The conclusion can provide theoretical support for carrying out the real ship trial of Gezhouba lock at the later stage.