The authors describe the CT findings in 10 cases of pulmonary aspergillosis which include allergic bronchopulmonary aspergillosis, aspergilloma and invasive pulmonary aspergillosis. CT reveals a more distinct radiologic-pathologic correlation than plain films and shows suggestive features of pulmonary aspergillosis earlier and in a more detailed fashion. Thus the use of CT in the appropriate clinical setting should allow earlier diagnosis than conventional radiography.