Single fetal demise occurs approximately 0.5-6.2% after 20 weeks of gestation in twin pregnancy. It raises not only mortality of co-twin but also perinatal morbidity and long term handicap after delivery. A-33-year-old monochorionic twin pregnancy, multigravida woman visited hospital because of heart anomaly of one fetus on ultrasound at 23 weeks of gestation. At 27 weeks, single fetal demise was confirmed and she had been taking weekly NST and ultrasound for live co-twin fetal viability. With closed observation, cerebral cystic lesion was found in live fetus at 35 weeks’ gestation, and immediate delivery was done at 35+6 weeks. Through neonatal ultrasound and MRI, ischemic cerebral cystic lesion and atrophy was confirmed. Also, synpolydactyly on left 5th toe was shown. For 5 months, there is no specific developmental handicap. We report our experience of delivery at 35 week’s gestation in monochorionic twin pregnancy with single fetal demise which was done immediately after confirming live co-twin’s ischemic brain damage during closed observation.