The author investigated the carpal bone and ephiphyses on the roentgenographic films. Several methods have been used in the study of carpal bones but I have calculated the numbers of ossification center. The subjects consisted of 259 boys and 239 girls from 3 to 13 years of age. The results are summerized as follows; 1. The number of ossification center were increased in aging both boys and girls. 2. Ossification tendency was more faster boys than girls and the difference of left and right hand were non significant. 3. The ossification of ephiphyses was completed in 4 years of age.