A typical case of naso-orbital-cerebral mucormycosis is described. This rare but serious disease mainly occurs in fragile patients, notably diabetics or those undergoing an immunosuppressant treatment. The cases recorded are therefore increasingly frequent. Mucorales, normally saprophytic, germinate in the nasal cavities due to an infection and then colonize the sinuses, the orbit, followed by the meninges. The diagnosis must be made before meningeal impairment when faced with a peri-orbital edema, the beginning of exophtalmy or oculomotor paralysis in high-risk patients with sinusal opacity. The diagnosis is based on the histology and the mucology which must be directed by the clinician: indeed, the histology of the naso-sinusal mucosa samples must be performed using special stains. The mycological samples must also be taken from special environments. Once the diagnosis is confirmed, the required treatment with high doses of intravenous Amphotericine B must be administered immediately, otherwise the evolution is fatal.