A rare case of rhinocerebral mucormycosis occurred in a 74-year-old diabetic male with gradually progressive right visual loss and total ophthalmoplegia. Computed tomography and magnetic resonance imaging revealed an invasive right orbital apex mass, destroying the medial wall of the orbit and extending into the right cavernous sinus and right middle fossa. Laboratory data demonstrated no signs of inflammation. A carcinomatous lesion originating in the paranasal sinuses and extending into the intracranial space was diagnosed. The mass was totally removed through a subfrontal approach to confirm the histological diagnosis and decompress the optic nerve. The histological diagnosis was mucormycosis. Despite aggressive medical therapy, dissemination resulted in mucor pleuritis and mucor encephalitis or meningitis. He died of septic shock and acute renal failure.