Objective To evaluate the therapeutic effect of calcitonin on osteoporosis in ovariectomized rats,and to investigate the association between calcitonin and IGF-1 and vitamin D.Methods 40 female 10-month old SD rats were randomized into 4 groups: sham operation group,ovariectomized(OVX) group,calcitonin(CT) group,Raloxifene hydrochloride group.The experimental model of osteoporosis was established by bilateral ovariectomy.Given CT 60 mg/kg body weight subcutaneous injection for 8 weeks,bone mineral densities of global and the lumber spine and femur neck were measured with Hologic dual energy x-ray bone densitometer in rat.Femur trabecular area,bone mineral deposition were measured by morphometry after the completion of therapy.Serum IGF-1 levels and serum 25OHVitD concentrations and lymphocyte vitamin D receptor contents were determined by ELISA.Results BMD of the lumber spine and femur neck in CT group and Raloxifene group were higher than that in OVX control group(P<0.01).Calcitonin increased trabecular area and bone deposition compared with that in OVX group.The serum IGF-1 and 25-OHVitD concentration in CT group and Raloxifene group were significantly higher than that in OVX control group(P<0.01).Conclusion Our findings indicate that the use of calcitonin demonstrated definite effect on IGF-1 levels and vitamin D metabolism and could be an effective therapy for osteoporosis.