Serum ferritin concentrations of 50 normal women and 90 patients with neoplasms of female genital tract were determined by radioimmunoassay. The mean value of serum ferritin in 23 cases of ovarian carcinoma was 402.04 micrograms/L, significantly higher than that of normal subjects and patients with benign genital neoplasms. Serum ferritin levels in patients with endometrial carcinoma, endometrial stromal sarcoma, and benign genital neoplasms were significantly higher than that of the normal subjects. There was a positive correlation between the serum ferritin level and the clinical stage of ovarian carcinoma. The serum ferritin determination is useful in the diagnosis, differential diagnosis and prognosis of ovarian cancers.