In 100 patients with trophoblastic tumors the functional activity of the adrenal cortex was examined before and after chemotherapy. Androgen-producing function of the adrenal cortex was found to be reduced as well as the absolute number of excreted 17-ketosteroids separate fractions and their ratio. The glucocorticoid function of the adrenal cortex shows a monotonous character. Only in patients having uterine chorion-epithelioma with metastases a reliable reduction of the fraction of 11-hydroxy-17-ketosteroids is noted before and after chemotherapy, while the per cent content of free 17-oxy-corticoid fraction is increased with regard to their total amount. Successful chemotherapy, associated with a lower titre of chorionic gonadotropins up to its complete disappearance, does not result in normalization of values characterizing the functional activity of the adrenal cortex.