Abstract: Objective To investigate the effects of resveratrol(RES)on bone mineral density(BMD), serum contents of nitrogen monoxid(NO)and nitricoxide synthase(NOS)in ovariectomized female rats.Methods Forty-eight Sprague-Dawley female rats were randomly divided into 6 groups:sham operated group, ovariectomized(OVX) group, OVX supplemented with 0.03 mg/kg diethylstilbestrol group(DES), and OVX groups supplemented with RES at dosage of 5, 15 and 45 mg/kg, respectively.The duration of exposure was 90 days.The BMD of lumbar vertebrae and serum contents of NO and NOS of the rats were measured at the end of the exposure.Results Compared with the sham operated group, BMD of the 4th, 5th and 6th lumbar vertebrae(0.141 4±0.001 1, 0.139 1±0.000 9 and 0.152 8±0.000 6 g/cm²)and serum levels of NO(8.190 5±3.814 8 μmol/L) and NOS(51.284 6±6.975 9 U/mL) of the OVX group were significantly decreased(P<0.05 for all).The BMD of the 5th(0.156 0±0.001 1 g/cm²) and 6th(0.173 3±0.001 5 g/cm²)lumbar vertebraes and serum contents of NO(18.624 3±2.613 0 μmol/L) and NOS(66.579 5±7.924 4 U/mL) of 45 mg/kg RES group were significantly higher than those of the OVX group(P<0.05).Compared with the OVX group, the NO content and NOS content of DES at 5 and 15 mg/kg of OVX rats were significantly increased(P<0.05).Conclusion Resveratrol has an inhibitory effect on lumbar vertebrae BMD in ovariectomized female rats and the mechanism of the effect may be related to the increased concentration of NO and NOS.