Anthropometric changes in infants, children, and adolescents from 1965 to 2005, during the period of 40 years, were reviewed. Those differences of adult heights were 5.3 cm from 168.9 cm to 174.2 cm in males, and 5.4 cm from 155.9 cm to 161.3 cm in females, respectively. However, the secular trends were more prominent in 13 years of age in males which was 18.6 cm, and in 12 years of age in females, 15.5 cm, which means that the age of puberty became earlier as compared to the previous generation. Looking at the changes of body weights in male and female, we can see that obesity became a serious health problem among Korean children and adolescents, particularly in males.