Based on field-observed data from Luohui Irrigation District, grey correlation analysis method was applied to analyze the relations between groundwater mineralization, depth and soil salt content. The model of soil water-salt dynamics was then established based on the analysis. The results show that groundwater mineralization was the main factor affecting soil salt contents, and also played an important role in transfer-ring salts. The interaction among various factors formed coupling relationship under the complicated condi-tion. As affected by external factors, it can be preliminarily determined that the soil of the Irrigation District was in desalination condition and in a relative stable state. The variation tendency of soil salt content differed from those of groundwater mineralization and groundwater depth. The quantitative model established in this study described well the response of groundwater dynamic to various factors with sufficient high accuracy. The combination provides a feasible method for analyzing the mechanism of soil water-salt dynamics under the condition of shallow groundwater during the crop growing season.