To ensure the normal operation of Yangshan Deepwater Port,maintenance dredging has been carried out for the approach channel annually in recent years.Based on the bathymetric survey data during 2017—2019,the distribution of shallow area and siltation characteristics of the channel excavation section are analyzed.It is pointed out that the siltation of the channel in the normal wind days is characterized by the seasonal variation law of “basic balance of erosion and siltation and local erosion in spring and summer,and mainly deposition in autumn and winter”;the siltation of the channel in the typhoon days is relatively obvious,and the degree of siltation is mainly related to the wind force and the moving path of the typhoon.Based on the hydrological data,the reason of channel siltation is discussed,which provides technical support for the dredging construction of Yangshan approach channel in the future.