Abstract: By placing different rare earth elements (REE) in different soil depth and different section across one slope in an indoor plot,one simulated rainfall was applied to study the spatial-temporal process both of depth and section erosion across one slope plot simultaneously.The results indicated that the REE tracer technology has high precision to quantify the spatial-temporal process of soil erosion; In earlier rainfall course,the development degree of sheet and rill erosion was general equation; Otherwise in the following course,the rill erosion was dominant in the total erosion,its average erosion acceleration and the average erosion rate was 15 and 9 times of sheet erosion,respectively; In the end of experiment,the rill erosion took up 90% of total erosion amount; The section of slope bottom occupying about 1/3 slope area was active erosion segment in this experiment.