The clinical and roentgenologic data of 22cases of acute pulmonary.mycosis are analyzed,with special emphasis on the X-ray manifesta-tions.Of the 22 cases,12 were roentgenographical-ly shown the so called"cottonball"nodularopacities in the chest,4 cavitation and 6 pneu-monia-like presentation.Furthermore,in 3cases there were many small,snow-flake-likepatchy opacities of heterogeneous density over60% of both lung fields.The lesions,bothunilateral and bilateral,were more concentratedin the middle and lower lung fields.Theselesions when enlarged with aggravation of thedisease would join to form large patches withina few days or even hours.