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An analysis is made of the variation regularity of soil moisture storage by use of the soil moisture storage data of 0 to 50 cm measured at both spring wheat field and atmospheric observation site at Huzhu County from 1977 to 2002. The results show that under the same climate background, the variation characteristics of soil moisture storage are basically consistent. The soil moisture storage of 0 to 50 cm from the atmospheric observation site is about 25 to 27 mm with minimum value being about 24 mm (from June to July) and the peak value being about 28 mm (September), and its annual variation curve shows an “M” shape. In the spring wheat field, the maximum value of 0 to 50 cm is 33 mm (March to April), and the minimum value is 21 mm (July) with the annual variation being about the same with the case of atmospheric observation. The results show that the drying method used in the spring wheat field can replace the neutron apparatus used in the atmospheric observation site.