The authors review the cases of 40 patients with AIDS who died in 1989, in order to establish the relationships between clinical picture, neuroradiological features and neuropathological findings. Neurological involvement was present in over 75% of the patients, with HIV-related encephalopathy and toxoplasmosis as the most frequent diseases (52.5% and 20.0%). With regard to the cases of AIDS dementia complex (ADC) the authors observed a good correlation between the severity of the clinical manifestations, central nervous system atrophy as observed on computed tomography scan and pathological findings. The survival of AIDS patients with ADC was higher when compared to patients without ADC, suggesting the time-relationship of ADC. AS in the case of toxoplasma encephalitis, a strong relationship between radiological and pathological findings was observed. The presence of toxoplasma encephalitis in patients with radiologic features of healed lesions confirms the need for life-long prophylaxis.