A 76-year-old man was admitted because of bloody sputum persisting for 3 months. Right upper lobectomy had been performed for non-small cell lung cancer (well-differentiated adenocarcinoma, pT1NOMO) 6 years prior, and the patient had uncontrolled diabetes. Chest computed tomography on admission showed a 1-cm nodule (fungus ball) in a cavitary lesion and consolidation with an air bronchogram were present in the right lung. Aspergillus flavus was detected in the patient's sputum, and laboratory tests were positive for Aspergillus antigen and antibody. Chronic necrotizing pulmonary aspergillosis (CNPA) was diagnosed in the surgically treated lung.