Although the long section from the Xingan junction to Longtoushan junction on the Ganjiang River is Longtoushan junction reservoir section，there are still many navigable safety problems，such as insufficient water depth in local area，obstruction of navigation by pre-regulated buildings and poor navigable bridge area. Considering the above problems，we put forward some regulation schemes，such as channel dredging，groin removal and route adjustment，and uses two-dimensional flow mathematical model of long river to conduct experimental research on the regulation scheme of Ⅱ level channel of the river reach. The results show that after the implementation of the regulation scheme，the navigable flow condition of the channel is improved and the channel scale can reach the construction standard. Specifically，the water depth within the designed channel line can meet the minimum navigable water depth of 3.8 m，the cross-current in the channel decreases，the bad flow state disappears，and the route is more straight.