A 62-year-old male was admitted for evaluation of a mass shadow on chest film. Chest PA showed $7{ imes}5cm$ lobulated homogenous mass in right upper medial area of lung. On chest computed tomography, there was a large irregularly lobulated mass with central necrotic low density area in apical segment of right upper lobe. Right upper lobectomy of the lung was performed. Partial adhesion to parietal pleura of posterior mediastinum and severe adhesion to right upper apicoposterior segment was found during the operation. Microscopic and ultrastructural studies(including immunocytochemical stains) of the mass revealed malignant fibrous histiocytoma.