A 27-year-old male with thymoma presented with recurrent severe anemia which required multiple transfusions. Bone marrow biopsy showed pure red cell aplasia with normal other cell lineages. He was diagnosed with pure red cell aplasia associated with thymoma and treatment with cyclosporine A was begun. After 12 weeks of treatment, his hemoglobin improved to 11.3 g/dL and the patient remained transfusion independent.