Cerebral aspergillosis is rare and usually misdiagnosed because its presentation is similar to that of a tumor. The correct diagnosis is usually made intra-operatively. Cerebral abscess with fungal infection is extremely rare and few cases have been reported, but it carries a poor prognosis. A 73 year-old man presented with decreased visual acuity and paresis of the right cranial nerve III. Magnetic resonance imaging (MRI) revealed a mass in the right cavernous sinus, extened to the anterior crainial fossa and the superior orbital fissure. During surgery, a well encapsulated pus pocket was found, and histopathological examination of the mass resulted in the diagnosis of aspergillosis. Despite appropriate anti-fungal treatment, the patient eventually died from fatal cerebral ischemic change and severe brain swelling. The correct diagnosis of cerebral aspergillosis can only be achieved by histopathological examination because clinical and radiological findings including MRI are not specific. Surgical intervention and antifungal therapy should be considered the optimal treatment. Early diagnosis and aggressive antifungal treatment provide good results.