Abstract: Objective To investigate whether probable cases of E.coliO157∶H7 infection were occurred in Hebei province, and to obtain surveillance information on the prevalence of E.coli O157∶H7 in animal hosts, food products and drinking water. Methods Municipal or provincial hospitals were selected. Cases of acute renal failure with diarrhea history was discovered through consulting the case histories of in-patients who entered the hospital between Junuary 1, 1998 and October 31, 1999, and a questionnaire was administered.Faeces of animal hosts,food products and drinking water were collected and inoculated on sorbitol MacConkey agar. Suspected colonies were inoculated in triple sugar iron agar,and then did the biochemical and serological identification. Results 41 probable cases of E.coli O157:H7 infection distributed in 8 cities were discovered. There was no rigid seasonality in the onsets of the ill-ness. Those probable cases were aged 8 adys to 78 years. 29 male and 12 female. 68.3% were farmers. 2060 samples of the faeces of more than 10 species animals were collected,and 2 strains of E.coli O157:H7 were siolated from raw pork. No strain of E.coli O157:H7 were isolated from the drinking water. Conclusion There ws a potential risk of outbreak of E.coli O157:H7 infection in Hebei province.