The undergrounds of nature and social economy for Tuweihe watershed were deal with in this paper, Meanwhile, the authors analysed the laws and characteristics of soil and water loss and made the study on the regionalization, the morphological,features of desert, the formation causes of wind erosion and desertization，and the ways and intensity of soil erosion, The exploitative way and control measures arrangement of soil and water loss were put forward inorder to supply scientific basis for controlling the tributaries of the sediment rich area with much coarse sand in the contiguous area of Shanxi，Shaanxi and Inner Mongolia,