This study was designed to evaluate the age-specific varicella-zoster virus (VZV) seroprevalence in children less than 5 years old who presented at a healthy child outpatient clinic and to compare the results with the data from other countries. The study was a cross-sectional study determining the prevalence of serum IgG against VZV in children who presented to the Healthy Child Outpatient Clinic of the Gazi University Medical Faculty and who were aged between 9 months and 5 years, in the 3rd-97th percentile as regards height and weight, not suffering from any disease, and without a history of vaccination against varicella. The information on the children was obtained from a questionnaire, by physical examination, and from patient files. Serum samples were obtained from babies and children at 9, 15, 24, 36, 48, and 60 months. The 295 serum samples were kept at -20 degrees C following centrifugation until used for serologic analysis (ELISA). The 292 children of the study group consisted of 168 males (57.5 per cent) and 124 females (42.5 per cent). VZV antibodies were found to be positive in 65 children aged between 9 months and 5 years (22.3 per cent); 22.0 per cent in males and 22.6 per cent in females with no statistically significant difference between the sexes (p > 0.05). The VZV seroprevalence was highest at the 48th and 60th months and this difference was statistically significant (p = 0.000).