Abstract: Indoor rain simulation experiments were conducted in this study under different slope degrees (10°, 15°, 20°, 25°), rainfall intensities using deionized water (1.5, 2.0 mm/ min) and slope lengths (5,10 m). The 3D laser scanner was employed to make real-time monitor after each rainfall event, and the effects of different slope degrees on rill erosion were analyzed. The results showed that the slope sediment yield significantly correlated with slope and could be expressed by binomial fomular. As the increased slope degree, the slope sediment yield increased firstly and then declined. The 3D laser scanner could calculate the data of rill development form and erosion amounts accurately. The development of the rill differed in slopes. The ratio of rill breadth to depth became smaller with steeper slope. There was significant positive correlation between rill density, rill erosion and the slope. The development degree of rill aggravated with steeper slope.