A rare case of pure red cell aplasia (PRCA) in association with pernicious anemia is reported. A 40-year-old man presented with typical clinical and laboratory features of pernicious anemia and received intramuscular injections of vitamin B12, with satisfactory response. Anemia recurred 6 months later despite continued therapy, and the patient was noted to have PRCA, which was treated successfully with two courses of high-dose bolus methylprednisolone therapy. His peripheral mononuclear cells before the therapy suppressed colony formation of early erythroid precursors (BFU-E) from normal bone marrow; such a suppressive effect was not found after recovery from anemia.