Navigation structures of navigation-power junction on the bended river usually face the problems of narrow river,multi-bend and short transition section.Yongning hydro-junction,located in Guangxi,is a station of the West River golden waterway with the pass capacity of class I.The dam site lies in the slightly bended river channel with a short straight waterway route,thus the navigation layout is rather difficult.According to the characteristics of the waterway of the dam site and the design navigation requirements,we study the overall hydraulic characteristics under operation and optimize the location of the dam based on the overall physical model.Meanwhile,combining with the channel scale optimization for a curving line into the gate and a straight line out of the gate and the shape optimization for the head of permeable separation levee,we achieve the goal that the flow conditions of upper and lower approach entrance satisfies the navigation flow requirements for less than 20 years’ return period,and solve the problems of the junction’s overall navigation layout.