Kisspeptin neurons in the brain stimulate gonadotropin-releasing hormone (GnRH) and luteinizing hormone (LH) release. Kisspeptin neurons are mainly localized in the anteroventral periventricular nucleus (AVPV) and arcuate nucleus (ARC) in rodents. Kisspeptin neurons in the AVPV induce LH surges to stimulate ovulation in females, and those in the ARC regulate LH pulses for follicle development and spermatogenesis. This review shows that androgen and aging negatively affect kisspeptin neurons in the ARC. Additionally, kisspeptin neurons regulate prolactin release through hypothalamic tuberoinfundibular dopaminergic (TIDA) neurons. For this reason, kisspeptin neurons may be involved in the development of hyperprolactinemia in older rats. Thus, kisspeptin neurons in the brain act as the main regulator for the release of LH, so their dysfunction leads to attenuated reproductive function.