目的　探讨用胫骨骨超声诊断骨质疏松症的标准及绝经妇女骨折的阈值。方法　对北京城区 40岁以上健康女性 3 99名和 70例有骨折史的绝经妇女进行胫骨骨超声速率的测定。　结果胫骨骨超声速率随着年龄的增加而下降 ;用 2 0～ 40岁健康年轻人胫骨骨超声速率的平均值分别减去2 0SD和 2 5SD ,165名 45岁以上的健康人中低于 2 0SD的占 16 7% ,骨折患者中占 80 0 % ;低于2 5SD的占 12 7% ,骨折患者中占 67 1%。结论　用本地女性胫骨骨超声速率的峰值减去 2 0SD作为骨质疏松症的诊断标准较适合 ;用 2 0～ 40岁年轻女性胫骨骨超声速率均值减去 2 0SD ,作为本地区绝经妇女骨折的阈值 Objective To explore the criteria for the diagnosis of osteoporosis with tibial bone ultrasound and the threshold of fracture in menopausal women. Methods Three hundred and ninety-nine healthy women over 40 years old in Beijing urban area and 70 postmenopausal women with fracture history were involved in the determination of tibial bone ultrasound velocity. Results The tibial bone ultrasound velocity decreased with the increase of age. The average tibial bone ultrasound velocity of healthy young people aged 20 to 40 were subtracted by 20SD and 25SD, respectively. Among 165 healthy persons aged over 45 years, less than 2 0SD accounted for 16 7%, 80 0% of fracture patients; less than 2 5SD accounted for 12 7%, fracture patients accounted for 67 1%. Conclusions The peak value of local female tibial bone ultrasound velocity is subtracted from 20SD as the diagnostic criteria of osteoporosis. The mean value of tibia bone ultrasound velocity of 20 ~ 40 year old female is subtracted by 20SD, which is regarded as the fracture of the menopausal women in this region Threshold