The channel entrance area obstruction of the downstream of Wuqiangxi junction has been a bottleneck that restricts the smooth passage of Yuanshui high-grade.Based on the test method of the physical model of the fixed bed flow,the current condition and the impeding characteristics of the river are analyzed.On the basis of the improvement plan of the permeable breakwater of the pile foundation,the plan of pile foundation diversion vanes for improving the navigation condition of entrance area is put forward.The oblique flow in the entrance area is weakened by combining barrier and diversion.Comparison of the test results before and after the implementation of the plan shows that the pile foundation diversion vanes has better effect on improving the navigation obstruction of oblique flow in the entrance area.