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Soil moisture measurement was conducted at the meteorological station and in farm land respectively from 2006 to 2008, for contrasting soil moisture mearements from the two cases under the same climate background. The relationship of soil moisture in the two cases is analyzed by the statistic method. The results show that there has marked consistency in the soil moisture from the two cases and there is significantly positive correlation in four seasons；in spring, the rate of difference in soil moisture between station and farmland measurements is larger in rainy weather than that without rainfall; in summer, the soil moisture measurements from 0 cm to 30 cm between station and farmland have a good relationship, and the difference rate is from -4.8% to 2.1% under the low vegetation condition; in fall, the difference rate becomes less and ranges from -4.3% to -1.4% under the low vegetation condition; in winter, the difference rate is larger, especially from 0 cm to 10 cm, greater than 17%. The mathematical model is established for the period with good correlation at various levels.