Sertoli cells are an important part of the male reproductive system. Except the function of promoting spermatogenesis such as supporting, providing nutrition and secreting, it also can maintain the immune privilege of testis through the expression of a special surface molecule named FasL. This feature aviods the immune response triggered by self antigen (germ cells) contacting with the body, which can be used to provide immune privilege environment for transplanted cells in areas other than the testis. In this article, we purified mouse sertoli cells, through adding different concentrations of IGF-I and IGF-I receptor inhibitor PPP, we study the role of IGF-I in the proliferation of sertoli cells. The results demonstrated that 30ng/mL IGF-I can promote the proliferation of sertoli cells while 2nmol/L PPP obviously inhibited the proliferation of sertoli cells. This result has a certain significance to obtain the high activity sertoli cells and increase the success rate of xenotransplantation.