Abstract: In order to understand the distribution characteristics of heavy metals in Tianjin coastal groundwater, the influence of seawater intrusion on the content of heavy metals and the influence of heavy metals on the health of residents, this study used statistics, correlation analysis and other methods to study the seawater intrusion situation in the study area, the characteristics of heavy metals in groundwater and the influence of seawater intrusion on the content of heavy metals in groundwater, and the groundwater was evaluated by USEPA's health risk assessment model. The results show that the order of heavy metal content is Mn>Ba>Zn>Cu>As>Ni>Cr>Pb>Cd, the groundwater in the study area was significantly affected by seawater intrusion, which resulted in the increase of Mn content in the groundwater. The carcinogenic risk of heavy metals was ranked Cr>As>Cd, and the health risk was ranked As Mn>Cu>Pb>Ba>Ni>Zn, among them, the health risk of Mn is much higher than that of other heavy metals, and seawater intrusion can have a great impact on the health risk. Overall, the carcinogenic risk of carcinogenic pollutants in the groundwater of the study area was greater than the health risk of non-carcinogenic pollutants.