Escherichia coli (E. coli) O157:H7 is a common cause of bloody diarrhea in developed countries. The aim of this study was to determine whether E. coli O157:H7 is a possible pathogen of bloody diarrhea in southern Iran. Out of 719 children with diarrhea, 243 (34%) patients with positive occult blood took part in our study. The polyclonal antibody test and polymerase chain reaction (PCR) were used to identify E. coli O157:H7. Stool cultures showed enteropathogens in 107 patients (44%). Shigella (34.3%) was followed by E. coli (8.6%), campylobacter (2%) and salmonella (0.4%). None of the E. coli species was of O157:H7 serotype. Antibiotic sensitivity of shigella species was 100% to ceftriaxone, ciprofloxacin and ceftazidime, 94% to nalidixic acid and 13% to co-trimoxazole. The results of the study showed that E. coli O157:H7 is not a cause of bloody diarrhea in our area.