Visceral leishmaniasis (VL) is endemic in parts of Islamic Republic of Iran. A cross-sectional seroprevalence study was carried out in children in Booyerahmad district in the south-west of the country. Serum samples were taken from 1628 children up to 10 years old from different areas in Booyerahmad in 2005–06. Anti-Leishmania antibody was detected in 50 out of 1628 children (3.1%) by direct agglutination test (antibody titre ≥ 13200). There was no significant difference in seropositivity between the sexes (2.8% males and 3.3% females). The highest rate of infection (5.2%) was in the age group 10 years. Further studies are needed to explore the reservoirs and vectors of the disease in this region.