In order to study the runoff-erosion process of saline-alkali silty loam slopes in a coastal reclamation area, a series of runoff scouring experiments were conducted to investigate the effects of slope gradient and upstream inflow on the soil detachment process. The results showed that the slope gradient and upstream inflow both had positive effects on the detachment rate but their effects were mutually restricted. The relationships between soil detachment rate, inflow scouring rate and slope gradient can be expressed by a power exponential function. The runoff energy consumption of unit width increased significantly with the increasing of upstream inflow rate and slope gradient(P < 0. 01). In addition, the relationships between the runoff energy consumption of unit width e_w, upstream inflow rate q and slope gradient θ can also be expressed by the power exponential function. The critical runoff energy consumption of unit width was 15~40 J/(h·m)for slopes between 5° and 15°, while it was zero for slopes between 20° and 40°. There was significant linear relationship between the soil detachment rate and the runoff energy consumption of unit width and the relationship can be expressed by the following function: R²=0. 82. Soil detachment started when the runoff energy consumption of unit width was very small for saline-alkali soil slopes in the coastal reclamation area.