Since the first cases of childhood AIDS were reported, the neurological involvement has been more frequently recognized. Several motor, intellectual and conductual changes as well as unexplained abnormalities have been described due to CNS infections. Findings have shown HIV to affect the CNS although it is unknown as to when the viral invasion actually occurs. This report describes the neurological manifestations found in pediatric patients with HIV infection at the Hospital Infantil de Mexico and their correlations with CT scans, EEGs, auditory evoked potentials, I.Q.s and postmortem findings. The medical records of 60 symptomatic HIV infected children, stages P0 to P2, are reviewed. Neurological abnormalities were found in 51 patients, 20 of which (39.2%) were due to perinatal infection with symptoms starting, on the average at 11 months 7 days (from the initial contact) taking into consideration in utero exposure. Nine cases (17.6%) were patients infected through transfusions with symptoms appearing on the average at 24 months 8 days; 2 cases (3.9%) were of unknown origin. The CT scans, EEGs and psychometric evaluations of the HIV infected patients correlated well with the clinical findings.