Regarding the difficult problem of plane layout in the confluence area of vertical branches and tributaries，the normal physical model is used to simulate the flow control and flow conditions for navigation in the confluence area.The inflow path of the tributary is optimized following the idea of split-flow，diversion and diffusion.The results of the recommended scheme show that when the recommended stream has no flow in main stream，the hydraulic complex can divert the tributaries according to the designed split ratio.When the main stream has incoming flow，the hydraulic complex automatically adjusts the incoming flow of tributaries cross downstream channel to join the main stream.The flow conditions for navigation in the confluence area meet the standard requirements under each working condition.The comprehensive optimization measures such as adding partition board，streamlined diversion island，diversion plate and so on can achieve the goal of flow control and improve the flow conditions for navigation in the vertical inflow confluence area.