This study was designed to compare the different somatotype growth of Chinese and Japanese boys aged 7 through 17. 2,074 subjects participated in it. Their somatotypes were analysed by using Heath-Carter method and their morphological varieties compared. Significant differences were found not only in their limb length and bone width, but also in their muscle circumferences and skinfolds. These differences showed the superiority of Chinese boys in ectomorph factor and the Japanese boys in endomorph and mesomorph factors respectively. The somatotype distributions of these two nations were also quite different at different ages, although they showed similar changing trend of somatotype around adolescent growth spurt.