The aim of this study was to determine whether heroin users have a higher prevalence of HAV infection than the general population in Spain, and whether injection is an independent risk factor. A cross-sectional cohort study was conducted between April 2001 and December 2003 in Spain that included 953 current heroin users aged 18-30 years. Dried blood spot samples were tested for HAV by ELISA. The prevalence of HAV infection (35.5%) was higher than in the general population of the same age. The logistic regression analysis did not show association between HAV infection and injection. HAV infection was associated with low educational level (OR=4.8; 95% CI=2.1-10.9) and other low-income variables. Injection is not an independent risk factor for HAV infection; rather, the principal determinants are socioeconomic factors. Consequently, HAV vaccination should be recommended not only in IDUs but also in non-IDUs depending on their socioeconomic characteristics.