The filling and emptying system is one of the important parts of the ship lock. To avoid the influence of the model scale effect in the ship lock hydraulics and ensure the safe operation of Qianwei ship lock at water level of 335 m，the prototype observation and commissioning of the hydraulic characteristics of filling and emptying system are carried out. Through the arrangement of 19 water level indicators in lock chamber，valve wells（service valve wells），upper（lower）miter gate，the hydraulic characteristics of filling and emptying system during the commissioning are obtained. The results show that when the filling valve is opened and closed at the recommended speed tv=4 min，the overfilling（over emptying）phenomenon occurs in the lock chamber obviously，which can be 0.40m and 0.10 m respectively，and it has an adverse influence on the safety of the miter gate and the ships passing through the lock.By optimizing the operation mode of the lock and valve，the phenomenon of over-filling（discharge）in the lock room is effectively alleviated，and the inertia of bilateral water filling（discharge）is reduced to 0.15 m and 0.10 m respectively. The paper puts forward the operation mode of the ship lock adapted to the water level of 335 m，which provides guarantee for the safe operation of the ship lock and the efficient navigation of ships.