1) Radiological evaluation of lung volumes was carried out on thirty Korean male patients with silicosis, and following results were obtained. 2) The mean radiological lung volume among those patient was 7,587ml. 3) When compared with the group of normal Korean male adults ranging from 31 to 55 years of age, the mean lung volume was increased by 2,346ml. 4) The lung volume of these patients was even slightly larger than that of the group of Korean athletes of all ages. 5) On the other hand, the vital capacity in patients with silicosis was markedly diminished, the mean vital capacity being 2,909ml. 6) The patients with silicosis also revealed emphysematous changes in the lung as well as increased residual volumes. The vital capacity was smallest in the latest stage.