The initial 5-years benefits of newly built protective forest are studied in this paper.The results show that the canopy interception coefficient is up to 19%,runoff rate ofoverland flow decreases by 10~19% and the soil water storage capacity increases 90% than slope wasteland in the early two years.The annuaI sediment yield is decreases 10~70% in the third year and will be up to 70~90% in the fifth year after the protective forest has been built.At the same time,the benefits of protective forest will increase along with forest age prolonging.