Abstract: A new method called Neutron Activate Analysis Tracer Method(NAATM)for studying soil erosion was formed through combination tracer method with neutron activate analysis technique,and the method was used to study the erosion process on slope.The research results showed that the changes of relative erosion amount with the distance from slope bottom to top accord with the Weibull distribution.The shape parameters of the Weibull distribution are mainly affected by precipitation,duration of rainfall and depth of runoff,and the scale parameters are related with aver age rainfall intensity and I₃₀.Soil erosion and deposition happened at the same time on slope.Generally,deposition is less under the short duration rainfall with high rainfall intensity than that of long duration rainfall with low intensity.The relationship between deposition amount at acertain slope position and its distance was derived.The runoff directly affects delivery ratio(DR).When the depth and coefficient of runoff is large,the DR approaches 1,otherwise the DR will decreases.