It is of great significance to solve the problem of runoff and sediment yield in Pisha Sandstone Area for the ecological security of the Yellow River Basin. The bare slope of Pisha Sandstone was taken as the research object, the field runoff plot measurement and three-dimensional laser scanning technology were used to analyze the micro-geomorphic change process and runoff and sediment yield characteristics under the 13 effective rainfall processes. The results showed that the average soil erosion depth was 26 mm, and the erosion area accounted for 95.27% of the total runoff area. The volume of soil loss caused by erosion was 0.019 m³/m². Runoff and sediment yield of Pisha Sandstone slope had a good corresponding relationship with rainfall intensity. Rainfall intensity and rainfall were the main factors affecting runoff and sediment yield. Influenced by the change of rainfall intensity, surface roughness, surface undulation and surface cutting degree all showed cumulative increasing trends with rainfall. The surface curvature was obviously affected by the intensity of single rainfall, but showing irregular fluctuations; there was a good positive correlation between runoff and sediment yield (r=0.539, P < 0.05).