Objective: To investigate into the prevention and cure effects of Bushen Ningxin Decoction(BSNXD) on postmenopausal osteoporosis.Methods: Postmenopausal osteoporosis model of female BALB/c mice(8-9 months age) were founded and afforded with the same volume of Chinese traditional medicine(BSNXD),17β-estradiol(E2) and saline(OVX),respectively.The skeleton,blood and uterus of each group were collected after 12 weeks of treatment.The uterus was weighed and analyzed histomorphometrically for differences.The level of IL-4 and IFN-γ in serum was detected by ELISA,the bone mineral density(BMD) of excised vertebra(L_(3-4)) and left femurs were measured by DEXA,right femurs were measured for norphometry of bone tissue,and semi-quantitative RT-PCR was performed to compare the level of mRNA level of osteoprotegerin(OPG) from tibia.Results: The level of BMD,area of bone trabecula and OPG mRNA in BSNXD group and E2 group were higher than that of OVX group.The IFN-γ level of BSNXD group was improved significantly,and the IL-4 level was reduced comparing to that of OVX group(P<0.01,P<0.05).Conclusion: BSNXD can selectively prevent and cure the postmenopausal osteoporosis with little side-effect on uterus.The mechanism of decoction is related to regulating the bias of Th1/Th2,enhancing the expression of OPG which can inhibit the activity of osteoclasts.