The navigable buildings in Wujiang Silin Hub，which are suitable for class IV channel，can not meet the requirements of the annual freight volume of the crossing dam according to class III channel planning，so the Silin second-lane navigation building is proposed to be constructed. In view of the poor condition of navigable flow at the entrance of the approach channel and the connecting section of the proposed navigable buildings，we conduct normal physical model research. Using a combination of water flow test，real-time flow field measurement，and self-propelled remote control model，we study the navigable water flow conditions and model manipulation in the upstream and downstream approaches of the navigable building and the connecting section under different working conditions，and obtain the optimal layout and navigable flow rate of the entrance area through program optimization，and conclude that the optimal layout of the entrance area is the modified program 3 layout form，and the maximum navigable flow rate of the entrance area is recommended to be 1 793.8 m3/s，which solves the key problem of navigability in the entrance area of the navigable building.