The convex hill slope was used as the object, using indoor runoff scouring experiments, the variation process of water erosion dynamics and variance of erosion sediment under different vegetation spatial configurations was studied. The results showed that the spatial variation of runoff velocity exhibited a fluctuating state, with first decreasing then increasing with distance between the hydraulic section and the slope top under bare-slope conditions. The most serious erosion was recorded on the upper part of the up slope and down slope. When the grass strip was planted at about 60%~80% of the up slope length, the impact on various runoff velocity was greater, and decreased by about 22%;by which water storage function is 12%, and sediment reduction function reach 69%. It could better exert soil and water conservation function by direct sediment interception and resulted in the lowest level of erosion in the experiment. The spatial variation trend of runoff and sediment was basically consistent with runoff velocity under different vegetation spatial configurations. With the increase of grass strip distance to the slope top, the runoff and sediment showed the first increasing then decreasing trend. The regulation effect of vegetation on erosion sediment transport was achieved through the regulation of the water erosion dynamic process. In the course of regulation, the vegetation spatial configuration altered spatiotemporal variation characteristics of runoff velocity, and thus played a significant effect on hydrological processes. The information of this study can be useful for better understanding the coupling relationship between vegetation, runoff scouring, and water erosion dynamics process.