The paper is concerned with the results of investigation into the nature of regeneration of function of the hypophyseo-gonadal system in 15 mature male Papio hamadryas, subjected to infusion of LH-RH agonists (buserelin, Hoechst A. G. Germany) and surfagon (All-Union Cardiology Research Center, USSR) using osmotic mini-pumps (Alzo Corp., Palo Alto, USA) for 5-16 weeks. Regeneration of this system was characterized by 3 main phases: latent; gonadal hyperfunction and return to the basal level of functioning. The time of phases was determined by a period of administration of the drug and individual features of functioning of the hypothalamo-hypophyseo-gonadal system. Unlike the sex glands, regeneration of hypophyseal gonadotropic function did not undergo the stage of hyperfunction but included the development of 2 phases of refractivity of gonadotropocytes to exogenous LH-RH, differing in the level of functional activity. Regeneration of function of the hypophyseo-gonadal system under basal conditions was followed by regeneration of a reaction of this system under the conditions of its activation.