Abstract: The mammalian ovary contains considerable preantral follicles which maybe the resources of large number of mature and fertilized oocytes to be developed and utilized has become a hot spot the current study. Research on the isolation and in vitro growth of the preantral follicles not only for women of reproductive insurance, but also to investigate oocyte development and apoptosis mechanisms in the cellular and molecular level, which would achieve the establishment of human eggs to provide experimental basis for the Treasury.

Key words: Preantral follicles, Isolation, In vitro growth