It is significant to determine the validation of a self-administered somatotype drawing for the simple assessment of childhood obesity in elementary school and clinical practice. Methods The subjects were 202 children(112 boys and 90 girls) who answered a questionnaire for somatotype drawing and were measured for body components with bioelectrical impedance. The somatotype drawing of children was analysed according to the three criteria of childhood obesity - BMI percentile, obesity index and percent body fat, respectively. Results BMI, waist-hip ratio, skeletal musclemass and protein mass had significant differences(p<.05) between boys and girls. Somatotype drawing had the highest correlation with BMI in both boys and girls, and also showed a high correlation with BMI percentile, obesity index and percent body fat. According to these criteria of childhood obesity, the somatotype drawing was the best consistent with the obesity index, next turn was the percent body fat and then the BMI percentile. Conclusions The validation of somatotype drawing for the assessment of childhood obesity was analysed according to BMI percentile, obesity index and percent body fat, and the somatotype drawing was the best consistent with obesity index in both boys and girls.