The process of spermatogenesis involves a complex interplay of several endocrine, paracrine, and autocrine factors. Endocrine regulation of spermatogenesis is finely controlled by the kisspeptin, gonadotropin-releasing hormone, the gonadotropins, and the testicular steroidogenic pathway. A thorough knowledge of the physiology is the key to successful management of patients suffering from disorders of spermatogenesis.