Owing to the geologyical, topographical and hydrological factors, it is inevitable to build hydraulic structures in the river bend. So it is very important to carry out studies of influences given by the bendway flow on the layout of the hydraulic structures. The three dimensional numerical simulation of the bendway flow outflowing from the sluice orifices located on the rapid river bend has been made by using the RNC κ-ε turbulent model. With the aid of simulation calculation, a comparative analysis is made of the flow characteristics and variation law related to flow velocity distribution, turbulent kinetic energy and pressure distribution as well as circulation flow passing through the sluice under the conditions of different gate openings and different flow discharges. Analysis results show that as the dam sluice is located on the upper river bend, the influence given by the sluice on the flow passing through the dam sluice is the minimal, but some prevention measures should be taken for protecting the area close to the convex bank slope of the lower outlet bend against erosion; and the influence given by the river bend on the flow passing through the sluice is the maximal. Therefore, the stability of the flow flowing through the sluice chamber, the gate safety operation and the cavitation damage to the piers should be taken as the key points in consideration and to which more attention should be paid in practical engineering. The numerical simulation results, which are in good agreement with the results obtained from the physical model tests, can meet the requirements of the calculation studies.