1. Primary and relapsed acute leukemia is increasingly being treated by bone marrow transplantation. Graft-versus-host disease (GVHD) is a major complication of bone marrow transplantation, occurring in 50% to 70% of cases. 2. Ocular complications of bone marrow transplantation are divided in those involving either the anterior or posterior segment. Because of associated total body irradiation with different forms of chemotherapy, these patients should be routinely watched by an ophthalmologist. 3. There is a high incidence of dry eye syndrome, viral keratitis, and trophic disturbances of the cornea. The presence of GVHD increases ocular involvement and its severity. 4. A study by Lopez and colleagues indicated that 62% of patients who survived at least 6 months after bone marrow transplantation for acute leukemia developed occlusive microvascular retinopathy.