Microsporidia are obligate intracellular spore-forming organisms. Several species of microsporidia cause human disease, mainly in immunocompromised hosts. The spectrum of disease varies from diarrhea, keratoconjunctivitis to disseminated infection involving multiple organs. CNS disease is a rare manifestation usually seen in compromised hosts as part of a disseminated infection. Only 12 cases of CNS microsporidiosis have been reported in the literature. Clinically, they usually present with signs and symptoms of encephalitis and seizures. Diagnosis often requires brain biopsy, but spores can occasionally be found in other sites. Albendazole and fumagillin have been successfully used in treating microsporidiosis at other sites, but their role in CNS infection is unclear.