Abstract: There is a serious sediment deposition in the wharf apron of an alongshore pile wharf. Based on the in-situ measured data of water depth and results of physical model tests and mathematic model calculation, the influencing factors on the sediment deposition in the wharf apron after construction of wharfs are analyzed taking the wharfs in Waigaoqiao Port in the Yangtze River estuary as an example. Analysis results show that the main factor of sediment deposition is the decrease of flow velocity in the wharf apron caused by pile resistance effects.