Senescence is an unavoidable physiological process that is caused by ageing of tissue and cells, declining of organ functions along with the increasing of age. In 1977, Besedevsky advanced the theory of immune-neuroendocrine network and hypothalamus-pituitary-gonad axis (HPG axis) is a important component in the network. The gonad functions decline gradually along with senescence, the function that the central nervous system regulate the HPG axis have also changed, the function of the whole HPG axis decline...