Using ANSYS finite element software，the whole model of the ship lift with ultra-high -lift rack and pinion including pillar，ship chamber，lifting system and the foundation is established，and the dynamic characteristics of the ship lift structure are calculated and analyzed. The results show that：1）The main low-order characteristic modes of the hoisting system and the ship lift include lateral swing，the vertical torsion and the longitudinal swing，and the natural vibration frequency of the cabin with a ship is less than that of the cabin without ship. 2）Comparing the pillar-foundation system model，modified HOUSNER simplified model with a ship，and the fluid-structure interaction model，it is found that the main mode frequencies of the overall structure model of the ship lift after considering the hoisting system are all reduced；the modified HOUSNER simplified ship model and the fluid-structure interaction model have similar natural frequency values，and the natural frequencies of simplified ship model system are less than the entity model of the ship.