A 45 year old woman was admitted to the emergency department of our hospital with an one and a half month history of gradually developing dyspnea. The chest x-ray showed pleural effusion which involved the middle and lower right pulmonary field. The patient underwent thoracoscopy (VATS) and a well differentiated papillary mesothelioma was diagnosed. Right pneumonectomy was performed and the conclusive histological diagnosis was extrasceletal Ewing sarcoma. The above case is presented because this Ewing sarcoma was primary located at the lungs given that the bone scanning was negative for neoplastic foci. Pneumon 2004, 17(1):94-100.