In mammals, ovarian follicle is made of an oocyte with its surrounding granulosa cells and theca cells. Follicular growth and development is a highly coordinated programmable process, which guarantees the normal oocyte maturation and makes it having the fertilizing capacity. The paracrine and autocrine between oocytes and granulosa cells are essential for the follicular development to provide a suitable microenvironment. Phosphatidylinositol-3 kinase /protein kinase B is one of these important regulatory signaling pathways during this developmental process, and bone morphogenetic protein-15 an oocyte-specific secreted signal molecule, which regulates the follicular development by paracrine in the mammalian ovary. The present article overviewed the role of phosphatidylinositol-3 kinase / protein kinase B signaling during the follicular development based on our previous investigation about protein kinase B /forkhead transcription factor forkhead family of transcription factors -3a, and then focused on the regulatory effects of bone morphogenetic protein-15, as a downstream signal molecule of phosphatidylinositol-3 kinase / forkhead family of transcription factors -3a pathway, on ovarian follicular development, which helped to further understand the molecular mechanism regulating the follicular development and to treat ovarian diseases like infertility.