The radiographic method of measuring and calculating total lung capacity (TLC) is a relatively simple procedure which can be performed by clinicians. To determine normal value of TLC radiographically in healthynormal Koreans, the author has performed measurement and calculation of TLC in 797 subjects comprizing 246 preschool children, 320 school children & adolescents and 231 adults. The results are as follows; 1. The values ofTLC were greater in males compared with females of the corresponding age, height or weight. TLC tended to increase with age until age 20 and no significant change was observed there-after. The mean value of TLC in females was less than that of males amounting to 68.3% in preschool children, 77.0% in school-children & adolescents and 67.3% in adults. 2. TLC increased gradually with height in all age groups. A linear relationship was noted between thetwo variables and the confficient of correlation in preschool and school children was 0.74 and 0.86 respectively. In adults, the approximation values of TLC were 1.0 x Ht3 in males and 0.9 x Ht3 in females. 3. No definite correlation between the TLC and the body weight in preschool children and adults in particular was observed. 4. Mean values of TLC in the adults obtained by radiographic method and physiologic method were 5,410±546ml and5,655±567ml, respectively and no significant difference in the values bewteen the two methods was demonstrable.