Abstract: Objective:Through surgical simulation in ovariectomized mice to women with postmenopausal osteoporosis, this paper comparatively studies the uphill and downhill running on bone mineral density and bone structure of ovariectomized mice.Method:32 (8-week-old C57 BL /6) female mice were randomly divided into 4 groups:sham operation group (SHAM) , ovariectomized group (OVX) , uphill running group (OVX + UP) and downhill running group (OVX + DOWN) .SHAM group mice were sham ovariectomized, and the remaining three groups of mice were ovariectomized.Training programs:OVX + UP group to do uphill running training, OVX + DOWN group to do downhill running training, 40 minutes each training, 5 times a week, trained a total of 8 weeks.After 8 weeks, the left femur and tibia metaphyseal bone mineral density was detected, the right tibia and the third lumbar vertebrae were made a hard tissue sections and the histomorphometry indexes were detected.Result:Compared with the SHAM group, OVX group were significantly lower in femoral and tibia metaphyseal bone mineral density, tibia and third lumbar histomorphometric indicators also showed signs of osteoporosis.Two exercise groups femoral and tibia metaphyseal bone mineral density significantly improved than OVX group, the tibia and third lumbar histomorphometric indicators also improved significantly compared with OVX group, OVX + DOWN group is better than OVX + UP.Conclusion:Treadmill exercise can prevent osteoporosis in ovariectomized mice, and downhill running is more effective than uphill running.