Cs-137 tracer method is simple, rapid and accurate, which has been widely used in soil erosion research. This article, taking Tiantai County as an example on the basis of non-farming soil erosion model, obtained the background value of Cs-137 (2382.02 Bq/m2) and soil Cs-137 profile distribution function (243.73e-0.113z), and also analyzed soil erosion and deposit law in different positions simultaneously. The results showed that soil erosion mainly occurred in the topsoil within 20 cm and the net loss of topsoil was higher than those of the middle and below slope locations, soil deposition occurred in the neighborhood of the foot - slope. Soil erosion rate at the different locations in the slope didn't increase with the length of slope simply, but changed with the surface vegetation structure and coverage.