The measurements and calculations of total lung capacity (TLC) by radiographic method were carried out in 231cases of normal Korean adults, 125 males and 106 females, and correlation with the conventional phsiologic methodwas investigated simultaneously in 8 cases. The following results were obtained; 1. The calculated value of TLC inmale was far larger than that in female, even in same age, height and weight group. The mean value of TLC infemale was 67.3% of that in male. 2. The TLC tended to show a gradual increase as height increased, and it had anapproximation to the value of 1X Ht3 in male and 0.9 X Ht3 in female. 3. There was no significant correlationbetween the value of TLC and age, and body weight either. 4. Each mean value of TLC in the radiographic andphysiologic method was 5410±546 and 5655±567, and there was no significant difference between the two meanvalues.