Due to the small section coefficient of the ship chamber，the ship entering and leaving the chamber is a complex three-dimensional water flow problem coupling with ship operation，and the hydraulics problem is very complicated. It is necessary to formulate reasonable ship draught control standards and ship navigation methods based on the ship squat to prevent the ship from touching bottom so as to ensure the safety of ship navigation and ship lift docking.Firstly，this paper introduced the navigation characteristics of the ship in and out of the chamber，analyzed the main affecting factors of ship squat，sketched out the theoretical analysis and formula derivation of previous research，and summarized relevant empirical formulas. Secondly，the calculation results of various empirical formulas were compared and analyzed for the process of ship entering and leaving the ship chamber. Finally，the future research direction and content on ship squat of ship lift were put forward.