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An analysis was made of the soil water data from the Henan Provincial soil water database from July 1997 to June 2003, and the variation regularities of soils water for various types of soils are discussed. The results show that the available soil water is the greatest for loam, the second for clay and the least for sandy soil. The soil water is influenced by underground water greatly. The areas with lower underground water level are less attacked by droughts. Based on the soil water data, the correction coefficients of soil water and the distributions of field capacities for various types of soils over Henan Province were determined, which were used a the forecast model of soil water.