A 58-year-old female who had a medical history of Diabetes mellitus for ten years and had used ciprofloxacin for urinary tract infection for the lost two months, was brought to the emergency room with headache and unconsciousness. At the time of attending she has a fever of 39.5° C, her pulse was 120/min per minute and blood pressure was 130/80 mm Hg. Her physical examination was normal except neck stiffness. In cranial magnetic resonance imaging there was a lesion concordant with encephalitis at her left hypocampal and hypothalamic regions. In lumber punction the cerebrospinal fluid (CSF) pressure was high. The cerebrospinal fluid study showed a total white cell count of 250 /mm³ (with 80% neutrophils and 20% lymphocytes), protein 74 mg/dL; glucose 131 mg/dL (simultaneous blood glucose 210 mg/dL); LDH 107 U/L; and lactate 37 mg/dL. In Gram and India ink stains of the CSF, no microorganisms were detected. Ceftriaxon 3x2 g/day and acyclovir 5x250 mg/day, both by i.v. route, were initiated as therapy. Upon growth of Aspergillus flavus in CSF cultures caspofungin was started. After two days lumbar puncture was repeated and CSF was re-examined. There was a decrease in glucose and an increase in protein values of CSF. In Gram stains of CSF there was no microorganism seen but again in cultures Aspergillus flavus grew. The patient died, and autopsy was hot permitted by her family. In diabetics using antibiotics for long term systemic fungal infections including cerebral aspergillosis should be considered.