The flow field in the entrance area of the downstream approach channel of Baoying Hub is complicated and chaotic.In order to ensure the safety of the inland ship’s navigation,we conduct a numerical simulation study on the overall waters of the downstream riverway of Baoying Hub,and compare and analyze the navigable flow conditions before and after the implementation of three optimization schemes,such as widening riverway,widening riverway+arranging diversion piers in the entrance area,and widening riverway+arranging partition dikes.The results show that in the original plan,the maximum rates of transverse and longitudinal flow are 0.95 m/s and 3.60 m/s when the flow is maximum,which exceed the safety limits of 0.65m /s and 1.60 m/s.The extension of the partition dikes causes the bad flow pattern of large backflow and cross flow at the end.Arranging diversion piers on the basis of the widening river is selected as the best optimization scheme.Compared with other schemes,this scheme can strengthen the momentum exchange of mainstream and local flow fields in the entrance area,reduce the rate gradient and the angle between the main stream and the entrance area,and significantly improve the flow conditions of the entrance area to ensure the safety of ship navigation.