Complications of tracheal intubation are well documented. However, iatrogenic aspiration of a broken metallic stylet following tracheal intubation has been infrequently reported. A 60-year-old woman, 10 days after shoulder arthroscopic surgery under endotracheal general anesthesia, was admitted to our hospital because of right chest pain. Chest radiographs showed a 8 cm length of metallic foreign body in the lower lobe of the right lung. Attempts at retrieval, including thoracoscopy, were unsuccessful. Open thoracostomy was performed. The removed foreign body was a part of metallic stylet. We report a case of iatrogenic aspiration of a broken metallic stylet.