Abstract: Polychlorinated biphenyls (PCBs) in molluscs may pose a potential threat to consumer health, but research is currently limited. In order to explore the threat of PCBs to consumer health in marine molluscs, GC-MS was used to determine the content of 7 kinds of indicator PCBs in 6 kinds of molluscs sold in Haikou, the pollution level was evaluated and the carcinogenic risk to consumers was assessed. The results showed that the content of seven indicator PCBs in marine molluscs sold in Haikou was 17.51-47.43 ng·g^-1 (dry weight), and the average content was 32.78 ng·g^-1. The composition of indicator PCBs in molluscs was dominated by medium and low chlorinated PCBs (trichloro, tetrachloro and pentachloro-PCBs), of which tetrachloro-PCBs are the most important component of indicator PCBs in marine molluscs in Haikou. They accounts for 38.49% of the total PCBs. The total content of PCBs in marine molluscs sold in Haikou was much lower than the USA and China's limits, indicating that the pollution of PCBs in molluscs was at an acceptable level. Compared with other studies in China, the total content of PCBs in marine molluscs sold in Haikou was at a medium level. The 5%, 50%, and 95% carcinogenic risk of indicator PCBs in molluscs sold in Haikou through the molluscs intake for adult consumers were less than the threshold value of the US Environmental Protection Agency, indicating that the carcinogenic risk of indicator PCBs in marine molluscs sold in Haikou was at an acceptable level for adult consumers.