Hexachlorobenzene （HCHs）, dichlorodiphenyltrichloroethane（DDTs） and poly-chlorinated biphenyls （PCBs） were determined in water, soil and mussel samples using GC-MS/MS, in order to investigate the concentrations, composition and distribution characteristics of legacy persistent organic pollutants （POPs） in different medium in the mussel mariculture area of the Huaniao Island, Yangtze estuary. The results showed that legacy POPs were widely detected in the samples, and the concentrations of HCHs, DDTs and PCBs ranged from 10.8 to 49.1, 169 to 900 and 10.4 to 34.4 ng/g（lipid weight） in mussel, 0.22 to 1.76, 0.07 to 0.29 ng/L and 9.45-51.8 pg/L in water, and 0.18 to 10.4, 2.62 to 69.6 and 0.40 to 0.69 ng/g（dry weight） in soil, respectively. DDTs were the main pollution compounds in mussel. The composition of target compounds in water and soil samples from the mariculture area reflected their exposure to residual pollutant emissions, with a dominance of highly chlorinated PCBs and DDT degradation products in mussels, which was associated with bioaccumulation characteristics. There were many significant positive correlations among HCHs, DDTs and PCBs in soils, as well as in mussels, reflecting the possible existence of similar sources of contaminants. The relationship between mussel tissues and non-biological medium can be seen in the principal component analysis. Health risk assessment showed that population ingestion of local mussels posed little risk of exposure and carcinogenic potential. This study can provide a basis for understanding the fate of legacy POPs among the different medium in the mussel mariculture area and the risk of mussel consumption by the population.