Abstract: We analyzed the residues of polychlorinated biphenyls (PCBs) in the seawater, sediments and cultured shellfish of Dong shan Bay by gas chromatography to evaluatethe risks of the residues to human health and edible safety. The results show that the PCBs contents at the bottom were higher than those at the surface of seawater, and thosein summer (August) were higher than those in spring (May). Overall, the PCBs contents declined from mid-bay to out-bay withthere is highly significant correlation between suspended matter contents and PCBs contents at the bottom of seawater. Moreover, PCBs contents at the surface of sedimentswere high in near shore but low in mid-bay and out-baywithihighly significant correlation between TOC contents and PCBs contents. The deleterious effects biology from the residues of PCBs were not obvious. In addition, there were clear differences of PCBs residuesamong cultured shellfish species. As for the capacity of PCBs enrichment, Saccostrea cucullata, Sinonovacula constricta and Paphia undulate were the best,then wereTegillarca granosa and Chlamys nobilis, and then Ruditapes philippinarum and Haliotis diversicolor. In conclusion, the cancerogenic risk index of cultured shellfish is acceptable. The levelof PCBs residuesin cultured shellfish in Dongshan Bay is medium among cultured shellfish in coastal Fujian Province.