In the process of downstream docking,ships in and out of the ship chamber caused by the surface fluctuation,water level difference docking influences the safe operation of the ship lift and ship berthing condition.To study the influence of the factors on the ship lift,we carry out the real ship test for overloading and no-load ships in different speeds in and out of the ship chamber and water level difference in and out ship chamber door opening and closing and obtain the variation characteristics of boat load undulation,synchronous shaft torque,as well as ship’s mooring force under corresponding working conditions,establish the interaction relation between the synchronous shaft torque and influential factors,and put forward safety control indices of the ship speed in and out of the chamber and the ship lift docking waterhead which satisfies the safe operation of Jinghong hydraulic ship lift