Abstract: OBJECTIVE To study therapeutic effects of collagen of antler plate on osteoporosis in ovariectomized rats. METHODS Wister female rats were randomly divided into sham-operated group, osteoporosis model group, positive control group, collagen of antler plate high, medium and low-dose group. Osteoporosis model was established by bilateral ovaries extraction. After 7 days, the rats were treated consecutively for 90 days with collagen of antler plate. The effects of collagen of antler plate on bone mineral density, alkaline phosphatase(ALP) activity and hydroxyproline(Hyp) content, bone histomorphometry, bone mechanics, body weight and organ index were observed. RESULTS Compared with osteoporosis model group, after treated by collagen of antler plate, bone mineral density increased significantly, ALP activity decreased and Hyp content increased, bone histomorphometry, and bone mechanics were significantly improved, body weight and organ index had no statistical difference. CONCLUSION Collagen of antler plate can treat osteoporosis in ovariectomized rats.