Based on simulated rainfall experiment,the processes of soil erosion dynamic variation on the loess hillslope were studied and the following results were obtained:(1)Soil erosion rate was increased with rainfall process under different rainfall intensities and it could be described with a logarithmic and linear combined equation.15 min and 35 min after rainfall beginning were the turning points of soil erosion rate with rainfall process.(2)Soil erosion rate was increased rapidly with the increase of rainfall intensity at different slope gradients and it could be described with linear equation.(3)Soil erosion rate varied with the increase of slope gradient at different rainfall intensities,having a trend of increase to decrease,and it could be described well with a logarithmic and linear combined equation.The critical slope gradient was about 25°.(4)Soil erosion rate varied with the increase of slope length at different rainfall intensities,having a trend of increase to decrease,and it could be described well with a logarithmic and linear combined equation.80 cm of slope length is the turning point of soil erosion rate.(5)Effects of rainfall intensity,slope gradient,and slope length on soil erosion could be described with a ternary linear equation.The influence of rainfall intensity on soil erosion is more significant than slope gradient and slope length and slope gradient is more important than slope length.