Osteoradionecrosis of the hyoid bone is a rare complication of therapeutic irradiation performed for head and neck cancer. In this article, we present a 52-year-old male patient who admitted with severe odynophagia following chemo-radiotherapy administration for tonsil carcinoma. Fluorine-18-fluorodeoxy-glucose positron emission tomography-computed tomography revealed a metabolic activity in hyoid bone. The pathological findings were consistent with fungal infection and hyoid bone necrosis. Hyoid osteoradionecrosis should be kept in mind in patients with intractable dysphagia following irradiation for head and neck tumors.