Since the advent of combination chemotherapy and central nervous system prophylaxis, more children with acute lymphoblastic leukemia have achieved prolonged remission. Prolonged survival has had result in extramedullary leukemia being recognized more frequently in patients still in bone marrow remission. Central nervous system and the testes have been the most frequently recognized antemortem extramedullary relapse sites. However, leukemic involvement of the ovary has received little attention, and the significance of ovarian-associated relapse in relation to the eventual outcome of the patient has not been ivestigated. Recently, we experienced an 11 year-old girl with acute lymphoblastic leukemia in hematological remission in whom a large ovarian tumor developed due to leukemic infiltration. We report in this case and briefly pertinent review of literature was done.