Pulmonary aspergilloma may usually deomonstrate the classic "air-crescent sign" in the conventional radiograph However, this lesion is often seen as a pulmonary nodule or is obscured by the surrounding scarred and fibrotic lung tissue, which may limit the value of the conventional techniques and hinder the diagnosis. We retrospectively analysed the plain film findings of 44 lesions of 40 patients and CT findings of 29 lesions of 26 patietns with pulmonary aspergilloma with special emphasis upon the atypical manifestation. The cases with classic "air=meniscus sign" in conventional radiograph accounted for 50% while 30% presented with a pulmonary nodule and 20% were untecognized forms due to surroundinjg parenchymal lesion. CT findings of 28 aspergillomas were analyzed according to the shape of the intracavitary space(space between the cavity wall and the fungal ball) and the fungal ball itself. the intracavity space showed " air-meniscus sign" (62%). Filling cavity (28%) perip eral air bubble (3%) and high density due to hemorrhage (3%) in descending order of frequency. The shape of the fungal ball itself showed homogeneous low density mass (62%) and spongeform or irregular air bubble contained mass (34%) CT was more accurate than conventional radiograph in the diagnosis and evaluation of number and location of atspergilloma particularly in the case of atypical presentation and was useful to assess the associate disease and to predict postoperative outcome.predict postoperative outcome.