BACKGROUND Despite a high frequency of anaemia, a positive direct antiglobulin test (DAT) and bone marrow hyperplasia HIV-infected patients, lack of reticulocytosis may cause underdiagnosis autoimmune haemolytic anaemia (AIHA) in them. This study was carried out to determine the prevalence of autoimmune haemolytic anaemia in HIV-infected patients and to compare the haematological/immunological characteristics of subjects with anaemia and those without. METHODS A total of 350 HIV-infected subjects attending the Lagos University Teaching Hospital who consented were recruited for the study. This included 250 subjects with anaemia (haemoglobin concentration <10 g/dl) as cases and 100 subjects without anaemia as controls. Five milliliters of venous blood drawn from each subject was used for the full blood count, reticulocyte count and DAT. RESULTS Subjects with anaemia had lower mean CD4 cell count (284.3 cells/μl) and higher mean reticulocyte per cent (1.5%) than the non-anaemic subjects. The frequency of reticulocytosis was higher in female subjects than in males. Only 0.8% (2 of 250) of the study group screened positive to DAT, p = 0.0339. None of the subjects in control group screened positive to DAT. CONCLUSIONS Autoimmune haemolytic anaemia is a rare complication of HIV infection in our geographical location.