A 73-year-old woman with myelodysplastic syndrome and diabetes mellitus, chronic renal failure and paroxysmal atrial fibrillation, received a diagnosis of facial cellulitis and was treated by antibiotics. However, her symptoms deteriorated. Facial magnetic resonance imaging (MRI) showed orbital cellulitis. She had weakness of visual acuity requiring changing the antibiotics. She also underwent steroid pulse treatment. Her symptoms temporarily improved, but she became comatose and died. Results of a molecular analysis of the residual cerebrospinal fluid indicated Rhizopus species infection. For immunocompromised hosts with refractory orbital cellulitis, mucormycosis should be considered as a differential diagnosis, and appropriate treatment should be promptly performed.