After studing on the distribution characteristics of soil agro-hydrology and the factors related to them in the loess region of Shaanxi province,the loess region of whole province is divided into seven sub-regions according to the leading index of soil physical clay content,and absolute moisture in the 100cm soil layer.and the differece between the precipitation and evapotranspiration. Soil agro-hydrological characteristics in each subregion are discussed,and the appropriate measures for soil improvement are put forward.