A systematic investigation of the incidence and type of peripheral and central auditory and vestibular disorders occurring in different stages of HIV infection was performed: 43 HIV-seropositive patients (14 were symptomatic with manifestation of AIDS or related complex and 29 were clinically asymptomatic) were compared with a matched control group of 33 HIV-seronegative homosexual volunteers. Among the symptomatic patients 8 (57%) out of 14 and among the asymptomatic HIV-positive patients, 13 (45%) out of 29 had abnormal results in various audiological, vestibular and electrophysiological tests. Only minor anomalies were found in 4 (12%) of the 33 seronegative homosexuals. Our results indicate a high incidence of neuro-otological disorders among patients suffering from AIDS. The numerous electrophysiological abnormalities found in asymptomatic HIV-seropositive persons suggest furthermore an early subclinical involvement of the auditory and vestibular systems.