Objective To explore the prevalenee of osteoporosis in the County Cadre in Lvliang analysis of bone mineral density using quantitative ultrasound.Methods Speed of ultrasound(SOS) and T-score of right RAD were measured by Omnisense QUS ultrasound in 990 County Cadre.Data were analyzed by t test,ANOVA and x2 test.Results The prevalence of osteoporosis in the subjects was 13%,with a higher rate in women than that of men.The prevalence rate increased obviously with aging.SOS decreased significantly with aging (P<0.01)