Abstract: Heavy metal pollution is a major issue in Marine environmental assessment. In order to understand the distribution and quality status of heavy metal content in seawater in mangrove areas of Wanning Lagoon, 20 surface seawater samples from mangrove areas in the investigation area were collected in mid-October 2022 to analyze seven common heavy metals （Hg, Cr, Cu, Zn, Pb, Cd and As） in that area .The distribution and pollution condition of seawater's heavy metals in mangrove area was evaluated by Comprehensive pollution evaluation method, Hakanson index and Risk quotient approach. The sources of heavy metals were evaluated based on correlation analysis and bidirectional stratified cluster analysis. The results showed that the average contents of Hg, Cu, Pb and Cd were 0.044, 14.975 , 0.695 and 0.628 μg/L respectively in the study area, and the detection limits of Cr, Zn and As were not reached at all stations.The distribution and pollution condition of heavy metal are as follows: mangrove area of Laoyehai Lagoon is better than mangrove area of Xiaohai Lagoon, natural forest area is better than other areas, and estuary area is worse than other areas, and the degree of Cu exceeded the standard and the degree of biological risk was relatively high among all heavy metal elements. Heavy metals mainly come from land-based anthropogenic activities such as fishery breeding and agricultural production, as well as atmospheric subsidence of port transportation and ship exhaust, and some areas are affected by point-source anthropogenic activities. The evaluation results can provide reference for the protection of mangrove ecosystem around Wanning Lagoon.