To study the effect of Kidney-Tonifying Bone-Strengthening Capsule on bone mineral density and cytokine in osteoporotic ovariectomized (OVX) rat models, confirming this medicine has preventive and therapeutic effect on postmenopausal osteoporosis (PMOP). Methods:Sprague Dawley rats, female, were randomly divided into six groups: sham operation group, ovariectomized group, ovariectomized + oyster calcium carbonate group, ovariectomized + low dose capsule group, ovariectomized + middle dose capsule group, ovariectomized + high dose capsule group, to observe bone mineral density and serum biochemical markers, and study the effect of ovariectomy on bone. Results:1.Change in bone density: 16 weeks after ovariectomy, the bone density and bone mineral content of the rat’s right hind leg thighbones in ovariectomized group were obviously lower than those of the sham operation group (P<0.01), indicating the model was successfully established. Compared with ovariectomized group, the middle- and the high-dose groups can significantly increase the level of BMC (P<0.05) of the said organ, meanwhile the latter can obviously increase the BMD level (P<0.05). 2. Change in serum E2 and IL-6: 16 weeks after ovariectomy, the serum E2 level in the ovariectomized group was significantly lower than that of the sham operation group (P<0.05), indicating the model was successfully established. The levels in the middle- and high-dose groups were higher than that of the sham operation group (P<0.05). 3. Change in uterus index and thighbones index: Compared with the sham operation group, the indices in ovariectomized group were obviously lowered (P<0.05), indicating the model was successfully established. Compared with ovariectomized group, the uterus indexes in the high dose group was increased, the thighbones index in high-, middle-and low-dose groups were all significantly increased. Conclusion:the Capsule can increase the wet weight of ovariectomized rat’s uterus while has no obvious effect to the dry weight. It also significantly increases the bone density level of exvivo thighbones, the serum E2 as well as IL-6 level from the ovariectomized rats and improves the Vitodynamics, having gonadal hormone like effect.