In this paper,expression and biological function of bone morphogenetic protein 15(BMP15) in mammalian reproductive system are summarized.BMP15 is expressed in the pituitary and promotes the synthesis of FSH.Secreted specifically by oocytes,it promotes the generation of granular cell and inhibits the differentiation of FSH-dependent cells.Mutations of BMP15 may cause multiplets or sterility in some species,indicating that BMP15 is an important factor regulating animal reproduction.It is necessary to investigate the mechanisms of BMP15 functions and the effect of mutations on reproduction in other species.