Gatrointestinal symptoms, which include diarrhea, are as common as respiratory symptoms in patients with HIV infection. Gastrointestinal symptoms may result from infections, neoplasma, HIV enteropathy or drug toxicity. Three HIV-infected patients admitted to our hospital complaining of diarrhea and fever. We confirmed their diagnosis as Campylobacter jejuni enteritis by bacteriological examination of their feces. All of them had eaten inadequately cooked meat in restaurants before the onset of their enteritis. Their symptoms immediately improved after the administration of antimicrobial agents. One strain of C. jejuni isolated in our cases, however, was resistant to ofloxacin. This case report suggests that we must counsel HIV-infected patients to avoid inadequately cooked food and observe resistant patterns of C. jejuni to antimicrobial agents in Japan in the future.