Mucormycosis is a rare fungal infection mainly developing in compromised hosts, and the associated mortality rate is high. We encountered a patient with rhinocerebral mucormycosis that had extended into the skull. Amphotericin B (AMPH-B) was markedly effective and saved the patient's life. The patient was a 51-year-old male with a past medical history of type-1 diabetes and he was being treated with dialysis for chronic renal failure. He visited his family doctor for left cheek pain, and received treatment for a diagnosis of left sinusitis and odontogenic maxillary sinusitis, but the swelling of the left cheek aggravated, and dysesthesia and left palatine mucosal necrosis developed. Thus, the patient was transferred to our department. On the first examination, Horner syndrome and cavernous sinus syndrome were observed, and multiple abscess in the left bucca, mucosal hypertrophy of the paranasal sinus, and lesions in the orbit and skull were noted on CT. Treatment for severe ondontogenic infection was performed, but mucormycosis was diagnosed on the second histopathological examination of the necrotized palatal region. The intravenous administration of AMPH-B (2.5 mg/kg/day) was initiated, and size reduction of the lesions was confirmed on CT after administration for 6 weeks. The lesions completely disappeared thereafter, but the patient died of another disease after 8 years. AMPH-B was markedly effective and saved the patient's life. When buccal cellulitis and sinusitis develop in a compromised host, it is necessary to take rhinocerebral mucormycosis into consideration. (C) 2016 Asian AOMS, ASOMP, JSOP, JSOMS, JSOM, and JAMI. Published by Elsevier Ltd. All rights reserved.