Abstract: A large scale field investigation of serotype distributions of V.parahemolyticus isolated from Shell-Fish and environment in the coasts of Zhejiang provance were reported. Of 792 strains were classified into is O-Groupes, 122 serotypes. The distributions of O-Antigen showed that there were close relative among the Sea-water, Shell-Fish and food poisoning patients and it should be emphasized that this organism is important clinically as a frequent cause of diarrheal disease not only resulting from ingestion of improperly processed Sea food but laso by other contamination dishes.