This study presents the case of rapidly progressing pulmonary aspergillosis in a 47-year-old woman who had healed cavitations of pulmonary tuberculosis in the right upper lobe. She had been treated for pulmonary tuberculosis seven years prior to admission. The initial manifestations of the disease on admission included cough, dyspnea, hemoptysis, pulmonary infiltrate, and renal failure. As anti-myeloperoxidase anti-neutrophil cytoplasmic antibodies (MPO-ANCA) were positive, she was diagnosed with ANCA-associated vasculitis and treated with corticosteroids. This treatment resulted in remission of the vasculitis. However, she developed new pulmonary symptoms and an enlarged cavitary lesion associated with the rapid formation of a fungal, ball-shaped shadow that was serially observed by radiological analysis. Pulmonary resection was finally performed because of acute progressive respiratory failure due to massive recurrent hemoptysis. A subsequent pathological analysis revealed a mass of hyphae with acute-angle branching, features consistent with Aspergillus, within the cavitary lesion, and she was diagnosed with pulmonary aspergillosis. The rapid development of pulmonary aspergillosis associated with the formation of an Aspergillus mycetoma should be attributed to the loss of normal immune mechanisms due to immunosuppressive treatment.