Abstract: The occurrence of tumor is not only closely related to a variety of carcinogenic factors from outside，but also keeps a close relationship with the body’s own immune response and genetic factors. B7-H4，a newly discovered immune regulatory proteins members of the family of B7， over-expresses in a number of malignant tumors. It acts as the second signal in the immune response， regulates immune activity and promotes the occurrence， development and prognosis of tumors. As described below，we discussed structure， function of molecules B7-H4 and its new progression with gynecologic malignant tumors.