The vertical and sagittal diameter of the vertebral body from the 12th thoracic to the 4th lumbar spine was measured by the true lateral roentgenogram. The material consisted of 110 normal Koreans ranging from the age of newborns up to adolescents, in which the vertebral body index (Ivb = v/s) and the intervertebral disk index (id = d/v) of each spine were measured and its interrelationship with normal growth rate was evaluated. The authors obtained the following results. 1. The vertebral body index showed gradual decrease with the advance of the age. It was significantly high in the group Ⅰ compared with other groups. 2. The difference between the boy and the girl was more significant at the 12th thoracic and 1st lumbar vertebral body than the othervertebrae in the group V. 3. Among children of more than 120 cm in height and older than 12 years of age, girls had a higher index of vertebral body than boys, the latter show a less pronounced vertical growth of the body. 4. The intervertebral disk index began to decrease after the 1st month of life possibly because of the accelerated vertical growth of the body from that period. 5. Of all the age groups, the intervertebral disk index showed a higher value in boys than in girls.