A case of warm autoimmune hemolytic anemia due to IgA antibody is described. The patient had clinical and hematologic signs of hyperhemolysis, but all specific tests were negative. The direct antiglobulin test was positive only when it was performed with anti-IgA monospecific antiserum. The autoantibody eluted from the patient's red cells showed anti-e specificity. The sensitivity of broad-spectrum antiglobulin serum and the possible hemolytic mechanisms of IgA-coated red cells are discussed.