Abstract: The new costimulatory molecule B7-H4,also called V-set domain containing T cell activation inhibitor 1(VTCN-1),is a member of the B7 family.B7-H4 can negatively regulate the immune response of T lymphocytes through inhibiting their proliferation and cytokine production.The expression of B7-H4 plays an important role in initiation,progression and regression of malignant tumors,including female malignant tumor,such as breast cancer,ovarian cancer and uterine neoplasm.The association between the female tumors and B7-H4 causes great concern in recent years.In this review,the function of B7-H4 in female tumor research and the potential target of B7-H4 in the diagnosis and treatment of female tumor are summarized.