In this study, the unit slope-gully system was used as the object, using indoor simulated rainfall experiments, combined with three-dimensional laser scanning technology and micro topography analysis technology, the difference of erosion sediment under different grasss trip position was studied.The results showed that some rational grass strips(p<0.05) influenced both runoff and sediment yield in the slope-gully system. The regulation functions on runoff and sediment with the grass strip on the middle lower part of the slope were generally clearer than those with grass on the upper part of the slope. The optimal position for grass strips in the slope-gully system was identified as 60% of the slope length. In this location, the grass strips could effectively reduce the runoff and sediment by 7.35% and 62.93%, respectively. The water storage function of the grass strip was weak; however, its direct sediment interception function was more effective, the water and soil conservation function was optimal.When grass strip was planted in the lower part of the slope, the severity of erosion sediment transport processes was eased, and the effect of grass strip on erosion was reflected.When grass strip was planted in the middle lower part of the slope, only 52% of the underlying surface was eroded,the severity of erosion sediment transport processes was eased significantly, the regulation of vegetatione ectively controlled the erosion formation and development.When grass strip was planted in the middle part and middle upper part of the slope, extremely aggravated erosion development.The information of this study can be useful for better understanding the optimal vegetation pattern.