Abstract: Abstract: Sediment size distribution greatly affects sediment transport and deposition. A better understanding of sediment sorting will improve the understanding of erosion and sedimentation processes, which in turn will improve erosion modeling. In this paper, using artificially simulated rainfall experiment, the sieved sand slope erosion and sediment grain size distribution and the change process were analyzed under the condition of 1.5 mm/min rainfall intensity, and the sieved sand slope erosion and sediment particle characteristics were explored, which aimed to further clarify the sieved sand slope erosion and sediment yield process. This paper studied the characteristics of sediment particles under different sand thickness, and there were 3 treatments, i.e. ST1 (sand thickness of 0.5 cm), ST2 (sand thickness of 1.0 cm), and ST3 (sand thickness of 1.5 cm). Malvern 2 000 laser particle size analyzer was used to measure the sediment particle composition, which was expressed by the mean weighted diameter (MWD). The results showed that most of coarse particulate matter was washed away within 0-10 min after the runoff production began; the sediment particle content of less than 0.054 mm was ST2