Monitoring regional cerebral oxygen saturation (rSO(2)) by use of near-infrared spectroscopy (NIRS) is a useful method for detecting cerebral ischemia. Tracheo-innominate artery fistula is a rare but life-threatening complication of tracheostomy. The surgical procedures for management of tracheo-innominate artery fistula include direct or patch closure of the fistula, ligation or division of the innominate artery, and anatomical or extra-anatomical reconstruction of the flow of the innominate artery. Division of the innominate artery is the best method to prevent postoperative recurrence of bleeding and infection. However, cutting off the innominate artery flow may cause brain ischemia. We present the case of a patient with tracheo-innominate artery fistula successfully treated by dividing the innominate artery while the rSO(2) was monitored. In this case report, we have shown that NIRS is a useful method for deciding the surgical maneuver for tracheo-innominate artery fistula.