Based on data of the leaching-pond experiment, this papercarried out multiple factor correlation analysis to irrigation quota, wetting layer depth and field water utilization coefficient, and established a regression model.The results showed that the field water utilization coefficient is negative correlation and with irrigation quota,and is positive correlation with the depth of planning-wetting.The relationship between the three can be described by bivariate regression model.The results insicated that it is not necessary to use the effective wetting layer depth of crop water requirement in peak period as the plan wetting layer to calculate the irrigation quota. Using the effective wetting layer depth in different period of crop grouth to calculate irrigation quota can effectively improve the utilization rate of field water.