Dysgerminoma is the most common malignant germ cell tumor in young women. The management of advanced-stage dysgerminoma challenges the gynecologic oncologist to achieve maximal survival, while maintaining childbearing potential. Radiation therapy has been extremely successful in curing dysgerminoma, but ovarian conservation is usually not possible. In contrast, various chemotherapeutic regimens have achieved high cure rates with continued ovarian function. Diagnosing recurrent dysgerminoma promptly so that salvage therapy can be initiated is important when conservative management has been employed. While alpha-fetoprotein and human chorionic gonadotropin have proven useful as tumor markers in some types of germ cell tumors, they have not been useful in patients with dysgerminoma. Serum lactic dehydrogenase (LDH) levels are known to be elevated in some patients with dysgerminoma. We treated a patient with Stage IIIC dysgerminoma whose initial serum LDH level was markedly elevated. After unilateral salpingo-oophorectomy with pelvic and paraaortic lymphadenectomy, followed by four cycles of VAC chemotherapy, her LDH level returned to normal. Her LDH level rose with disease recurrence and returned to normal again with salvage BEP chemotherapy. This is the first report to document the utility of serial LDH measurements in detecting disease recurrence in patients with ovarian dysgerminoma.