In order to understand the impacts of different grass strip widths on the soil and water loss of in purple soil sloping farmland, taking the Agrostis stolonifera grass strips paved on purple soil slope as the research objects, and through the indoor simulated scouring, we study the impacts of different grass strip widths and drainage scouring flows on the slope rill erosion morphology and the effects of sediment and flow reduction. The bare slope was used as the control group. The results showed that:(1) With the increasing of grass strip width, the rill depth decreased first and then increased, while the rill width, rill length and width-depth ratio showed a contrary tendency. In addition, the rill width, rill length and rill depth increased with the increasing of discharge, but the change of width-depth ratio was not obvious. (2) When the discharge flow was small (4 L/min), the runoff and sediment yield rate decreased with the increasing of grass strip width, and the outflow runoff decreased by 48.41% by for the 100 cm grass strip, which was the greatest. When the discharge was large (8 L/min), the 75 cm grass strip had the minimum runoff and sediment yield rate, which had the maximum reduction rate of runoff (20.07%) and sediment (58.11%). (3) Under interception of the grass strip, the runoff and sediment yield rate and soil erosion rate had significant correlation with rill width and rill depth. Compared with runoff interception and reduction, the grass strip had more significant impact on sediment interception and reduction. From these results we concluded that the grass strip was very efficient in reducing the runoff and sediment, and had a good control effect on water and soil loss of purple soil sloping farmland.