About 326 elementary school boys and 299 elementary school girls of an age ranging from 6 to 13 are included in this flat foot prevalence study. Results of the study are categorized in three groups, namely city centers, rural areas and suburbs. For the assessment of flat foot, footprint test is used. Prevalence of flat foot was 35.5% among girls and 28.5% among boys. Flat foot was associated with child age, residency and body mass index (BMI). Flat foot prevalence was highest among 6-year-old children, and lowest among 11-year and older children (P < 0.05). Flat foot prevalence was lower among children living in rural areas and children with low BMI value (P = 0.001). More overweight and at risk of overweight children had flat foot compared to normal and underweight children (P < 0.05). Familial predisposition was also noted for flat foot; 16.1% of children with flat foot had a familial history of flat foot, while this rate was only 5.6% in families of healthy subjects (P = 0.001). © 2010 Springer-Verlag.