Background: Street children are at increased risk of mortality and morbidity due to a variety of diseases such as hepatitis A as a result of both the circumstances that made them vagrant and as a direct consequence of life on the streets. The aim of study was to determine the seroprevalence of hepatitis A and its associated risk factors in street children, Isfahan, Iran. Methods: A total number of 348 subjects, aging between 7-18 years old, were enrolled in a cross-sectional study. They completed a demographic and risk factor assessment questionnaire and undertook serological screening for hepatitis A. Chi-square test and t-test were used for statistical analysis in SPSS15. P-values < 0.05 were considered significant. Findings: The subjects included 228 (65.5%) boys and 120 (34.5%) girls with mean age of 12.97 ± 3.34 years. In addition, 15.8% of the participants were sexually active and 3.7% reported using drugs. Overall, the prevalence of hepatitis A virus antibody (HAV-Ab) was 91.4%. Statistical correlations were seen between HAV-Ab and gender, education, nationality, sexual activity, and drug abuse. Conclusion: The prevalence of positive HAV-Ab among the studied street children was 9-fold higher than the rate among the peer group in general population of Isfahan (10.63%). Educational programs and access to health care facilities should thus be considered for theses children. Keywords: Street children, Hepatitis A, Iran