Two men presented with decreasing libido and impotence. Endocrine evaluation showed that they both had low levels of serum testosterone and a prolactin-secreting adenoma. Transsphenoidal removal of their tumors resulted in normalization of serum prolactin and testosterone concentrations and normalization of sexual function. These patients represent the first two nonacromegalic men with prolactin-secreting tumors and hypogonadism in whom surgical resection of their tumors resulted in a complete clinical and biochemical remission. We discuss the effects of elevated prolactin on male sexual function.