Fungi of the genus Aspergillus are ubiquitous Saprophytes in nature. Many reports since the first report of human aspergillosis by Slayter[1847], have suggested that this is not a rare condition. Author have reviewed 15 cases of pulmonary aspergillosis obtained in Dept. of Thoracic Surgery, Busan University Hospital from 1966 through 1976, and taken literatural consideration. The results were obtained as follows. 1. Ages ranged from the first to sixth decades, with the majority [73.3%] in the third and fourth decades. The male to female ratio was two to one. Both upper lobes were predominantly involved [80%]. 2. Hemoptysis was the most common symptom and it was appeared in 66.6%. 3. Only 4 cases [26.7%] were take correct diagnosis before operation. Remained cases were difficult to be taken the correct diagnosis preoperatively because of lower discovery rate of aspergillus in application on immunological typical X-ray findings and non-specific symptoms of them. 4. Preoperatively, 8 cases [53.3%] were taken diagnosis as pulmonary tuberculosis. 5. Underlying diseases were present in 11 cases [73.3%] and 6 cases of them were pulmonary tuberculosis.[KTCS 1978;1:18-25]