Abstract: Limited by the shoreline planning,Yalan wharf only chooses site in the branch between Ruxi shoal and upper shoal at Jiepai reach,which is accompanied by dredging of harbor basin and approach channel. As a kind of special wharf embedded in the shoal,the downstream is often close to the shoal regulation buildings,such as spur dikes,and the riverbed evolution and channel conditions of the reach are complex. In order to study the influence of the wharf pile group and large-scale dredging on the channel conditions,this paper adopts the physical model test of Jiepai reach to determine the scope and degree of influence,including the changes of water level,velocity,branch diversion ratio and riverbed erosion and deposition before and after the implementation of the engineering are analyzed. The results show that the engineering construction has little impact on the navigation flow conditions of the main shipping channel of the Yangtze River. However,due to the combined action of wharf piles and dredging of approach channel,the left edge of upper shoal head is scoured. To a certain extent,scouring affects the shoal protection function of spur dike,and compensation engineering needs to be implemented to mitigate this adverse impact.