A young HIV-infected patient presented with a severe auto-immune haemolytic anaemia with both warm and cold auto-antibodies, an infrequent category of anti-erythrocyte auto-immunity. Serological findings were compatible with the presence of a low-titre, high-thermal-amplitude anti-I cold-reacting antibody and a pan-reactive warm-reactive auto-antibody. Immunochemical characterisation of the warm antibody failed to identify any membrane protein acting as auto-antigen. This is, to our knowledge, the first reported case of mixed-type auto-immune haemolytic anaemia in a patient with HIV infection. Overt haemolysis is a very rare complication in HIV-infected patients, despite the high prevalence of a positive direct antiglobulin test reported in these patients. This suggests that HIV infection is a condition in which anti-erythrocyte auto-immunity is a serological finding without haemolytic effects in the large majority of cases.