Cytomegalovirus (CMV) infection of the retina is a well recognized complication in patients with the acquired immune deficiency syndrome but is rarely seen after bone marrow transplantation (BMT). Among a variety of drugs ganciclovir so far appears to be the most effective therapy for CMV retinitis, but in previous studies relapses occurred in all patients in whom ganciclovir was interrupted. We report the clinical findings in a 22-year-old BMT recipient who developed bilateral exudative CMV retinitis 64 days after BMT despite prophylactic treatment with high-titer CMV-immunoglobulins and transfusions of CMV-negative blood products and donor bone marrow. During a 12 day course of treatment with 7.5 mg/kg/day of ganciclovir the CMV retinitis improved and viruria ceased on day 4 of therapy. In contrast to the previous reports, CMV retinitis in this patient continued to improve even after ganciclovir was stopped and eventually complete healing of all intraretinal lesions as well as total reconstitution of the visual acuity was achieved. He is now free of disease and without relapse of CMV retinitis more than 1 year after transplantation.