A 40-year old woman was admitted with a history of elbow, wrist, knee pain and prolonged morning stiffness. Rheumatoid arthritis (RA) diagnosed before five years, had been treated with non-steroidal anti-inflammatory agents and low dose corticosteroid. On hospital admission, routine chest x-ray showed a 4x4 cm solitary mass in the right pulmonary. A diagnostic thoracotomy was performed. The histological examination showed a typical carcinoid tumor. This is the third carcinoid tumor case reported to be associated with RA.