Hiccups are common benign and usually transient phenomenon that occur in nearly everyone. However, persistent or intractable hiccups can cause multiple problems including malnutrition, weight loss, fatigue, dehydration, insomnia, and wound dehiscence. We have experienced a case of postoperative persistent hiccup. The patient was formerly diagnosed tongue cancer and developed persistent hiccup after partial glossectomy with modified radical neck dissection and a radial forearm free-flap operation. He was unsuccessfully managed using pharmacologic methods, and then we tried phrenic nerve block guided by ultrasonography and a nerve stimulator because the surface anatomy of neck was deformed by the previous operation. Thirty minutes after the block, the hiccups disappeared.