Zygomycosis of the basal ganglia should be recognized as a syndrome in intravenous drug users associated with a culture-negative cellular CSF, fever, lethargy, and lesions apparent on contrast-enhanced CT scans of the head. The infection is most likely the result of intravenous inoculation of fungal spores. This entity is different from the rhinocerebral zygomycosis seen with diabetes mellitus and other diseases. In the rhinocerebral form, there are external signs of the disease with involvement of the orbit, paranasal sinuses, and palate. In these drug users, infection was directed to areas deep within the brain.