The prevalence of antibodies to hepatitis A virus (HAV) was investigated in 114 children (59.7 per cent males) aged 4-6 years, in the campus area of Middle East Technical University, Ankara, Turkey. The prevalence of hepatitis A antibody in this age group was 11.4 per cent (13/114). The rate of immunized children against hepatitis A was 3.65 per cent (5/137). In conclusion the prevalence of anti-HAV demonstrates the susceptibility of other preschool children to hepatitis A. This may be a cause for considering hepatitis A vaccination before preschool attendance in Turkey.