Helicobacter cinaedi (formerly Campylobacter cinaedi) was first detected in the fecal flora of homosexual men. Since 1984, 11 case reports of H. cinaedi bacteremia have been published; most cases have presented as a nonspecific febrile illness in homosexual men infected with the human immunodeficiency virus (HIV). We identified seven additional cases of H. cinaedi bacteremia in two Denver hospitals within a 5-year period, which suggests that this illness is not as rare as was previously thought. Six of these cases of H. cinaedi bacteremia occurred in homosexual men who were infected with HIV. Four patients presented with the distinctive cutaneous manifestation of multifocal cellulitis, and two patients had monoarticular arthritis. Microbiological diagnosis of this infection was delayed by the slow growth of the bacterium in nonradiometric blood culture bottles. Although the patients' bacteremia was prolonged, their response to treatment was excellent. In contrast to campylobacter infections in HIV-infected patients, H. cinaedi bacteremia did not relapse after a course of effective therapy. H. cinaedi bacteremia should be suspected in HIV-infected individuals who present with an indolent febrile illness, particularly in the presence of multifocal cellulitis and/or arthritis.