Abstract: For the sake of identifying the dynamic behaviors of soil water and salt, and then providing a theoretical basis for the strategies of water saving irrigation and farm water management in the coastal area of North Jiangsu Province, a long-term and continuous monitoring of soil water content, soil salt content and groundwater level was conducted in the typical coastal area of Dafeng City, Jiangsu Province. The relationships between soil salt dynamics and factors of waters balance were discussed according to the data monitored and those (precipitation, soil surface evapotranspiration data) provided by weather station in Dafeng City. The results showed that soil salt of surface layer was highest and its salt fluctuation was most activated, and soil salt gradually decreased with depth. Soil water content and groundwater level were increased in summer due to rich precipitation and little evapotranspiration, while decreased in winter due to little precipitation and plenty evapotranspiration. The salt in groundwater was the main source of salt accumulation in the profile. Groundwater level and water complement amount were the main impact factors of soil salt at 0-40 cm depth. Groundwater level and evapotranspiration were the main impact factors of soil salt at 60-80 cm depth. The desalting role caused by precipitation significantly affected the soil at 0-40 cm depth, while the salt accumulation role induced by evapotranspiration affected the soil in the profile. The study provides scientific basis for the recede of soil salinization in the coastal area of North Jiangsu Province, and possesses great significance in directing local agricultural production.