In order to predict the variation of soil moisture content and adopt effective measures in time, a forecast model for soil moisture was studied and developed on the basis of the model of Xinanjiang according to the meteorological data of the Three-River Plain region. The model was tested with the data of 1979-1984. A comparison between the calculated values and the practically measured values was made, and their correlations were analyzed. According to the meteorological data of the region in spring of 1985, Prediction of moisture content of soils in Baoqing County was made with the model, the results is recorded in the table 3.