Survival times for patients with leukemia generally have improved in recent decades, and this improvement has been attributed to an enhanced understanding of the genetics driving the cause of the disease and improved combinations of chemotherapy and targeted therapy. Durable control of systemic disease in blood and bone marrow has significantly improved survival, but extramedullary relapse can pose therapeutic challenges for which radiation therapy can have an important role. This report discusses the current role of radiation therapy for patients with leukemia, specifically the extramedullary manifestations of leukemia.