The authors present the results of evaluation of the skeletal maturation in 579 children aged 1-5 years. Bone maturation was evaluated, based on skeletal age, by the Tanner-Whitehouse II method (Tanner et al., 1975). It was found that girls up to the age of three years had lower and in the more advanced age groups higher values of skeletal age than boys. Boys were retarded as regards skeletal age in relation to chronological age on average by 0.28 years and girls by 0.25 years.