Due to the special water and sediment inflow conditions and unique geographical environment, the Gaocun- Aishan reach of the lower Yellow River has become a typical “hump” reach. Taking the water and sediment data of hydrological stations in the lower Yellow River from 1990 to 2020 as the research object, this paper focuses on the water and sediment inflow and section morphological characteristics of Huayuankou-Gaocun and Gaocun-Aishan sections in the lower Yellow River, and establishes the functional relationship between sediment discharge ratio, river sediment inflow coefficient and river facies coefficient using the formula of non-equilibrium sediment transport rate. The results show that after the Xiaolangdi Reservoir was put into use, the sediment inflow in the hump reach of the lower Yellow River decreased sharply. Based on this situation, the numerical relationship between the sediment discharge ratio and the sediment deposition in the lower Yellow River is constructed and the power function formula of sediment discharge ratio, sediment inflow coefficient and river facies coefficient is further established. This formula can calculate the scouring and silting changes of each reach more accurately using the parameters such as water and sediment inflow conditions and river section morphology of the lower Yellow River.