A 15 month old child with a history of multiple infectious diseases was admitted to hospital for investigation of pyrexia and general ill health. She was anaemic with a persistent neutropaenia associated with hypergamma globulinemia, indicating intense autoimmune activity: cellular immunity was abnormal with a normal total lymphocyte count but a very low T4/T8 ratio. HIV serology was positive; the virus was isolated from a lymph node biopsy specimen. The parents for the child were HIV positive and the father went on to develop full blown AIDS. The neutropaenia was constant over the two years of follow-up and granulo-immunofluorescence studies suggested an autoimmune origin. In contrast to autoimmune thrombocytopaenia and haemolytic anaemia, autoimmune neutropaenia is a rare condition. A few cases have been reported in adult AIDS. Our case is of additional interest as it illustrates the vertical mode of transmission of AIDS.