Autoimmune hemolytic anemia (AIHA) is a disorder associated with the destruction of red blood cells (RBCs) by autoantibodies. We report a rare case of AIHA in an infant rhesus macaque (Macaca mulatta) which received a continuous administration of four drugs, a dopamine agonist. dopamine receptor inhibitor, and two gamma-aminobutyric acid receptor inhibitors into the brain during the course of neurophysiological experiments. The main clinical findings were severe anemia and splenomegaly. Hematological and serological examinations revealed the appearance of peripheral erythroblasts and autoantibodies against RBCs. Medical treatments, including washed RBC transfusion and corticosteroids, transiently improved the animal's anemia, but euthanasia was decided on 331 days after the start of the experiment. The pathological findings revealed severe anemia, splenomegaly, and extramedullary hematopoiesis in the liver and kidneys. These findings and the clinical course suggest that this anemia was a warm-antibody type of AIHA induced by the administration of the drugs for the neurophysiological experiment.