The reason,distribution and harmfulness of Soil and Water Loss in Song-Liao valley was analysed in this Paper,Regionat Preventive measures was proposed based on the results of the analysis,According to resemble princeple oferosion Factors,Song-Liao Valley was divided in to five systematic region of soil and water ercoion with each corre-sponding control pattern,Main direction of attack to provent soil and water loss in the valley was suggested in thepaper.