ObjectiveTo explore the mechanism of Tibetan medicine Ershiwuwei Guijiuwan against osteoporosis in ovariectomized rats through the classical Wnt/β-catenin signaling pathway. MethodForty-eight 3-month-old SD female rats were randomized into model group （equivalent volume of normal saline）， sham operation group （equivalent volume of normal saline）， estradiol group （0.1 mg·kg^-1 estradiol valerate）， and high-， medium-， low-dose Ershiwuwei Guijiuwan groups （800， 400， 200 mg·kg^-1， respectively）. For the modeling， some adipose tissue near the ovaries was removed in the sham operation group， and ovaries were excised in other groups. Administration （ig， once a day） started two weeks after the operation and lasted 12 weeks. After sampling， based on hematoxylin and eosin （HE） staining， the morphological changes of the right femur and lumbar spine of the rats were observed. The enzyme-linked immunosorbent assay （ELISA） was performed to detect the serum levels of rat tartrate-resistant acid phosphatase 5b （TRAP5b）， collagen type Ⅰ C-terminal peptide （CTX-Ⅰ）， bone alkaline phosphatase （BALP）， amino-terminal propeptide of type Ⅰ procollagen （PINP）， and bone Gla-protein （BGP）. Real-time fluorescence quantitative polymerase chain reaction （Real-time PCR） was performed to examine the mRNA expression of β-catenin and Runt-related transcription factor 2 （Runx2） in femur， and Western blot to detect the protein expression of β-catenin， Runx2， and low-density lipoprotein receptor-related protein-5 （Lrp-5）. ResultCompared with the sham operation group， the model group showed disordered and sparse bone trabecula with fewer connections， decrease in serum levels of BALP， BGP， and PINP （P<0.01）， increase in levels of CTX-Ⅰ and TRAP5b （P<0.01）， reduction in mRNA expression of β-catenin and Runx2 in femoral tissue （P<0.01） and protein expression of Lrp-5， β-catenin， and Runx2 （P<0.01）. Compared with the model group， estradiol and each dose of Ershiwuwei Guijiuwan increased the volume of bone trabecula， made thebone trabecula closely arranged， reduced the loss of the trabecular meshwork， raised the serum levels of BALP and BGP （P<0.01）， and lowered TRAP5b level （P<0.01）. PINP level was significantly increased in the high-dose Ershiwuwei Guijiuwan group and estradiol group （P<0.01） and CTX-Ⅰ level was significantly decreased in the high-dose Erwenwuwei Guijiuwan group and the estradiol group （P<0.01） compared with those in the model group. The mRNA expression of β-catenin in femoral tissue and protein expression of Lrp-5 and β-catenin in estradiol group and three Ershiwuwei Guijiuwan groups were significantly increased （P<0.05， P<0.01）， and the levels of Runx2 mRNA and protein were significantly increased in the high-dose Ershiwuwei Guijiuwan group and the estradiol group （P<0.01） compared with those in the model group. ConclusionTibetan medicine Ershiwuwei Guijiuwan is effective for the osteoporosis in ovariectomized rats， which may be related to the classic Wnt/β-catenin signaling pathway. It affects bone metabolism by up-regulating the expression of osteogenesis-related genes in the signaling pathway.