Abstract: Based on the soil moisture data at 0~200 cm depth from 14 stations in the dry farming region of eastern Gansu Province in years 1989 to 1992, the soil reservoir moisture storage capability and its change rule of the different climate patterns in the region are studied according to the atmospheric precipitation-soil moisture circulation system. The paper gives both the soil moisture storage standards under the different degrees of agricultural drought and the deficit of the storage capability, which provide the base for the exploiting and utilizing of soil reservoir potential.