The central sea area of Ningbo-Zhoushan Port is surrounded by islands on all sides,and ships can only enter and exit through a few navigation gates.The current conditions for navigation of ships at Guanmen and Guishan Navigation Gate on the east side,as well as the maximum navigation ship types for Jintang Bridge and Xihoumen Bridge on the south side are relatively strict.By observing the tidal currents in the waters of Guanmen and Guishan Navigation Gate,we set up the working conditions for ships to queue up in sequence,and analyze the passage capacity of the two navigation gates.Then we carry out the adaptability analysis of the navigation scale and current codes of Jintang Bridge and Xihoumen Bridge,and study the starting surface of clearance scale,the height above the waterline of ships,the slope and deflection of bridges,the net height of bridges,and the real-time measurement system of the maximum height above the waterline of passing ships.The results show that the passage capacity of Guanmen and Guishan Navigation Gate is suitable for the development of port planning in the central sea area.It is suggested to build a dynamic approval system for large ships crossing bridges,in order to unleash the potential for the development of water shorelines.