BMP-1/TLD-related metalloproteinases played key morphogenetic roles via proteolytic maturation of a number of ECM proteins and activation a subset of growth factors of TGF-β superfamily.Recent data indicated that BMP-1 expressed in sheep ovarian follicles and showed a protease activity.The aim of the current study was to characterize the mechanisms of buffalo BMP-1 gene in action during follicular genesis.A 3195 bp buffalo BMP-1 mRNA fragment was firstly cloned and sequenced by RT-PCR, which contained a whole 2967 bp CDS.The multi-alignment results showed that BMP-1 is highly conserved among different species both in nuclear tide and amino acid level.BMP-1 locates in oogonium of fetal buffalo ovary, as well as in the granulosa cells and oocytes of adult ovary from primordial to large antral follicles.The further study showed that BMP-1 promotes cell cycle and proliferation, and inhibits the apoptosis of granular cells.Adding BMP-1 recombinant protein to the culture medium of granulosa cells.increased the expression of the key cell cycle regulators such as Cyclin D1 and Cyclin D2.Cell apoptosis pathway related genes such as Cytochrome C, Fas, FasL and Chop.etc were down-regulated both in mRNA and protein levels.While it also up-regulated the expression of PAPP-A, IGF system and VEGF.etc, which play an important role in selection and dominance of follicles.The contrast results were observed by adding BMP-1 antibody investigation.This study suggests BMP-1 has the potential to promote the selection and dominance of buffalo follicles by regulation the proliferation and apoptosis of granulosa cells.