To accelerate the desalination improvement of coastal tidal flats in Jiangsu Province, a typical area was selected for field location tests. The variation rules of groundwater depth and mineralization under specific hydrological and environmental conditions were statistically analyzed. The results show that the rainfall on coastal tidal flat areas in Jiangsu is abundant, and the spatial and temporal distribution of rainfall is uneven. The rainfall from May to September accounts for 73% of the annual rainfall. The correlation coefficients between groundwater depth and rainfall, evaporation and the water level of the Liangduo River near the study area are 0.94, 0.78 and 0.51, respectively, showing extremely significant correlation. The groundwater mineralization is significantly correlated with rainfall and evaporation with the correlation coefficients of 0.79 and 0.66, respectively. It is also significantly correlated with groundwater depth with the correlation coefficient of 0.42.