Prolactinomas are the most frequent pituitary tumors and their frequency varies with age and sex, occurring most frequently in females between 20-50 yr-old. In men, hyperprolactinaemia is often present for many years without symptoms, as generally the most important symptoms are the decrease in libido and/or sexual potency both underestimated by the majority of the patients. Prolactin (PRL) plays a role in the process of spermatogenesis, and normal serum PRL levels are required for normal testicular function. On the other hand, hyperprolactinaemia has multiple negative effects on the gonadal axis. As a consequences hyperprolactinemic males show alteration of sexual potency and seminal fluid quality. Cabergoline treatments is able to induce normalization of PRL levels and a reduction of tumor mass in the majority of patients and consequently restoring the normal semen quality and ameliorating the quality of life of men with pituitary PRL-secreting adenoma.