Objective:To investigate the impact of Qing'e Pill(青娥丸,QEP) on the cancellous bon microstructure and its effect on the level of β-catenin in a mouse model of postmenopausal osteoporosis.Methods:Ninety-six 8-week-old specific pathogen free C57BL/6 mice were randomly divided into 4 groups (24/group):sham,ovariectomised osteoporosis model,oestradiol-treated,and QEP-treated groups.Three months after surgery,the third lumbar vertebra and left femur of the animals were dissected and scanned using micro-computed tomography (micro-CT) to acquire three-dimensional (3D) parameters of their cancellous bone microstructure.The impact of ovariectomy,the effect of oestradiol and QEP intervention on cancellous bone microstructure,and the expression of β-catenin were evaluated.Results:The oestradioland the QEP-treated groups exhibited a significant increase in the bone volume fraction,trabecular number,trabecular thickness,bone surface to bone volume ratio (BS/BV),and β-catenin expression compared with those of the model group (P＜0.05).In contrast,the structure model index,trabecular separation,and BS/BV were significantly decreased compared with those of the ovariectomised osteoporosis model group (P＜0.05).No differences were observed in the above parameters between animals of the QEP-and oestradiol-treated groups.Conclusions:The increased β-catenin expression may be the mechanism underlying QEP's improvement of the cancellous bone microstructure in ovariectomised mice.Our findings provide a scientific rationale for using QEP as a dietary supplement to prevent bone loss in postmenopausal women.