In 1997, prevalence of and risk factors for hepatitis A virus (HAV) infection were evaluated in 146 homosexual and 286 heterosexual men attending a Sexually Transmitted Disease (STD) Clinic in Rome, Italy. Total HAV antibody (anti-HAV) was detected in 60.3% of homosexuals and 62.2% of heterosexuals. After adjustment for the confounding effects of age, years of schooling, number of sexual partners, use of condoms, and history of STD, homosexuals were not found to be at increased risk of previous HAV exposure than heterosexuals (OR 1.1; 95% CI 0.7-1.9). Independent predictors of the likelihood of anti-HAV seropositivity among homosexuals and heterosexuals were: age older than 35 years and positive syphilis serology which is likely a proxy of lifestyles that increase the risk of faecal-oral infections. These findings do not support a higher risk in homosexual men but could suggest a role for the vaccination of susceptible patients attending STD clinics.