Mycobacterium xenopi is a nontuberculous mycobacterium (NTM) that rarely causes pulmonary disease in Asia. Here we describe the first case of M. xenopi pulmonary disease in Korea. A 66-year-old man was admitted to our hospital with a 2-month history of productive cough and hemoptysis. His past medical history included pulmonary tuberculosis 44 years earlier, leading to a right upper lobectomy. Chest X-ray upon admission revealed cavitary consolidation involving the entire right lung. Numerous acid-fast bacilli were seen in his initial sputum, and M. xenopi was subsequently identified in more than five sputum cultures, using molecular methods. Despite treatment with clarithromycin, rifampicin, ethambutol, and streptomycin, the infiltrative shadow revealed on chest X-ray increased in size. The patient's condition worsened, and a right completion pneumonectomy was performed. The patient consequently died of respiratory failure on postoperative day 47, secondary to the development of a late bronchopleural fistula. This case serves as a reminder to clinicians that the incidence of NTM infection is increasing in Korea and that unusual NTM are capable of causing disease in non-immunocompromised patients.