The composition and working principle of a sealing frame system for a ship lift were introduced.The pressure retention of the sealing frame system was realized by mechanical and hydraulic devices.The sealing frame system mechanical and hydraulic coupling simulation model was built by using AMESim and the model was used to analyze the influence of the key factors,such as the spring stiffness,hydrocylinder diameter and oil temperature,on pressure retention characteristics.It provides reference for the selection of system components and the later debugging operation and fault diagnosis.