Abstract: Leptin, a novel molecule, is a protein hormone produced by the obesity gene. This protein and its receptor show that they play an important role in many biological action. Recent study found that leptin as a signal effects on the adequacy of nutritional status and reproductive function are thought to be mediated centrally via neurotransmitters. Leptin concentration is associated with hypothalam?-pituitary-gonad axis, follicular development, implantation, polycystic ovary syndrome and male infertility. Study leptin in the function of reproductive system will benefit to reveal the regulation of clinical infertility and provide the new rapeutic strategy for human assisted reproductive technology.

Key words: Leptin, Reproductive endocrinology, Polycystic ovary syndrome, Assisted reproductive technology, Male infertility