Abstract: Hydrodynamic fields are computed with the topography of the year 1984, 2010 and 2020 based on FVCOM model. The hydrodynamic changes near the waterways of Zhoushan and Jintang are studied in details. By comparison, the hydrodynamic fields near Jintang Channel have some significant changes owing to natural and human factors. Analysis on the three Section Runoff in the channel of Ningbo-Zhoushan sea area, it can be easily found that the flow in the three periods has a cumulative effect. After further analysis, it can be assumed that the change of the hydrodynamic field may cause sediment deposition along southern coast of Hangzhou Bay and the port of Ningbo on the condition that the sediment-carrying capacity of flow at low tide is enough, and it would affect the use of the harbor nearby.