The working valve is the throat of the filling and emptying system of the ship lock，and its performance directly affects the safe and efficient operation of the ship lock.In this paper，a whole three-dimensional mathematical model of the filling and emptying system and a partial three-dimensional mathematical model near the valve are established based on the Liujiang Honghua second line ship lock project.By comparing the water level within the lock chamber，the filling flow rate and unsteady pressure process after the valve，it is shown that the whole three-dimensional model can better simulate the culvert pressure change process after the valve compared with the results of the partial three-dimensional model calculation.The calculation is carried out for the continuous opening of the bilateral valves and the continuous opening of the unilateral valve in the water filling process.It is found that there is no negative pressure at the top of the culvert after the valve under the most unfavourable working conditions to meet the design filling time.The calculation method can be used as a reference for numerical simulation of ship lock valve hydraulics，and the simulation results can provide technical support for safe operation of the similar projects.