The incidence of foot deformities in children from Bratislava schools (Slovakia). The most common foot deformity is flat foot (pes planus), high arch of foot (pes excavatus) and juvenile bunion (hallux valgus). In our study, we focused on the presence of these deformities in the population of Bratislava children aged 6–12 years. We used the method of Chippaux-Šmiřák index for analysis of the arch of foot. The results indicate that in the measured children aged 6–12 years the normal arched foot is most common. The occurrence of flat foot is more frequent than high foot and more common in boys. The high body mass has a major impact on long-term loading arch of the foot and it is the main cause of flat foot. The angle of the thumb magnifies in older girls, which increases the risk of hallux valgus deformity.