Abstract: Objective The present study was designed to know the infection status of Enterohaemorrhagic Escherichia coli，serotype O157：H7 and the distribution feature of the bacterial types in Zhejiang province to conducive to the establishment of corresponding strategies of its prevention and control．Methods Faeces of patients with diarrhea were collected aI diarrhea clinics of different prefectures and cities in Zhejiang province from May to October during which enteric infectious diseases were highly prevalent And The serotype O157：H7 strain was isolated and cultured and the virulence gene was detected by PCR Results Two strains of Enterohaemorrhagic Escherichia coli，serotype O157：H7 were detected in the population examined from 1998 to the day when this study was completed．Detection of virulence gene by PCR revealed positive SLT2 and Hly and negative SLTl Conclusion The human Enterohaemorrhagic Eschedchia coli，serotype O157；H7 wim virulence gene isolated this time is different from those observed previously．Suggesting that some characters of O157：H7 have changed and these strains are more detrimental to people's health