Taking Guyuan experimental area in southern Ningxia as an example, the comprehensive harnessing benefits of small watershed were studied. The results show: In the comprehensive harnessing, the key of harnessing are adjustment of land use structure and rational arrangement of agriculture-forest-pasture distribution. This structure of land use is seted as 3:2:5, according to the used area above. By the theory of eco-system engineering and combination with practice of the agriculture-forest-pasture structure, the land productivity could be improved by 2~5times as that before, runoff and sediment obviously reduce.