Pure ovarian dysgerminomas with associated elevation of human chorionic gonadotropin (hCG) are rare, and their optimum management is unclear. We report here a 24-year-old woman with stage III dysgerminoma of the ovaries, with bulky intrapelvic disease, paraaortic adenopathy, and elevated pre- and postsurgical serum beta-hCG titers. Following administration of whole abdominal-pelvic and mediastinal irradiation therapy, the patient's adenopathy regressed, her serial beta-hCG titers returned to normal, and she has remained free of disease for the past 30 months. Histopathological studies revealed a pure dysgerminoma with scattered giant cells which were negative for hCG by immunoperoxidase staining. The literature is reviewed with reference to the significance of elevated hCG levels, the presence of giant cells in association with dysgerminoma of the ovary, and therapeutic implications. Serial determinations of beta-hCG titers may prove to be as valuable in the management of these patients as they are in patients with testicular tumors.