In this study, combined with the measured data and theoretical analysis, the physical model experiment is setup for the Wudingmen sluice in Nanjing. After that, the problems of sediment deposition is formed and studied. The bend upstream induced by the sluice changes the flow pattern that can be improved by setting a diversion wall. The results also show that the river bend infect the flow pattern. Meanwhile, there are obvious recirculation zone on the both sides of river and the size of left zone is larger than the right, which results in the heavier deposition of left riverbed than the right side. In addition, the weak river flow dynamics makes the sediment deposition heavier. By setting the diversion wall upstream the sluice, the size of the recirculation zone is reduced and the flow pattern is improved. This study can provide reference for improving the upstream flow pattern and reducing sediment deposition.