Serial cehalometric roentgenorgams of 40 Korean children (25 males, 15 females) were employed to study the growth changes of the cranial bases. As a result of this study, the following conclusions can be made : 1. The mean size of the cranial bases in males was larger than the females, especially at the age of 13. 2. In both sexes, growth of the cranial bases was seen from 6 to 13 years of age and the growth of the posterior cranial base (S-Ba) was larger than the anterior cranial base(S-N). 3. Variation in the changes of the saddle angle (Ba-S-N) was exhibited with males showing a marked tendency toward a decrease in saddle angle size.