Excavating channels for entering and leaving harbor and harbor basin can change the original riverbed topography and elevation,thereby altering its hydrodynamic conditions and sediment erosion and deposition,and affecting its navigation conditions.In response to this issue,we take Xiaogu Wharf in Qianwei as a basis,use Mike21 to build a two-dimensional numerical model of water and sediment,and analyze the water flow pattern and sediment accumulation before and after excavation of channels for entering and leaving harbor and harbor basin engineering,as well as after changing the depth,width,angle,etc.of the channel for entering harbor.The results show that excavation of channels for entering and leaving harbor and harbor basin has a relatively small impact on the overall water flow and sediment conditions of the original main channel,and a relatively small impact on the navigation conditions for ships entering and leaving harbor.Different excavation conditions have different impacts on the water and sediment conditions of channels for entering and leaving harbor and harbor basin.Different excavation angle conditions have a greater impact on the water and sediment conditions of Xiaogu Wharf,and the 30° layout can better meet the navigation flow conditions of Xiaogu Wharf.