The invention relates to a Chinese traditional medicine extract for preventing and treating osteoporosis and its preparation method and application. The extract mainly comprises rhizoma atractylodis volatile oil, total alkaloid of Phellodendron amurense, and total saponins of radix achyranthis bidentatae and total sterone of radix achyranthis bidentatae; can be used for preventing and/or treating osteoporosis and relevant disorder, which has gradually become important pathogenesis influencing life-quality. The extract has easily-accessible raw materials, simple preparation, high extraction efficiency, strong pharmacological action, stable quality, high safety, low toxicity, and controllable quality. The invention comprises three Chinese traditional medicines in classical prescription, come to optima activity for resisting osteoporosis, reduces adverse side effect, and provides a new medicament source for preventing, diagnostic ting, detecting, protecting, treating and researching these diseases and their relevant diseases.