Thymomas rarely present with chest pain due to hemorrhage. This could cause shortness of breath if it ruptures into the pleural space, and is best managed surgically. We describe the case of an 83-year-old woman who presented with such symptoms. Computed tomography showed a ruptured mediastinal mass with pleural effusion. She was managed successfully by thoracotomy with excision of the mass and drainage of the effusion. Histopathology revealed a ruptured thymoma with infarction and necrosis.