A 72-year-old male with a past history of artificial pneumothorax for pulmonary tuberculosis at the age of 25 was referred to our hospital for the clinical signs of pain and swelling of the back. His neuron-specific enolase values were high in both serum and pleural effusion. The computed tomography image showed a tumor mass arising from the wall of chronic pyothorax. The tumor was resected including the wall of the chronic pyothrax and right chest wall with several ribs. The tumor was 7.2 x 7.0 x 3.0 cm in size and the pathological diagnosis was non-Hodgkin's lymphoma diffuse large cell, B-cell type. Postoperative chemotherapy and radiation therapy were performed but he died of recurrence and metastasis of the tumor 5 months later after the operation.