Osteoporosis, as a systemic bone disease with high incidence rate and high disability rate, has become a research hotspot in recent years. The daidzein in soybean isoflavones can bind with estrogen receptors, simulating the prevention and treatment of osteoporosis with estrogen-like effect. Its mechanism of action includes promoting osteoblast formation and differentiation by activating the Wnt signaling pathway, increasing bone density, and improving bone tissue health; inhibiting osteoclast differentiation and slowing down bone resorption by reducing receptor activator of nuclear factors κB ligand/ osteoprotegerin ratio, downregulating the expression of macrophage colony-stimulating factor (M-CSF); collaborating antioxidant and immune regulation to achieve the goal of preventing and treating osteoporosis. In addition, different doses of daidzein have different effects on bone density and osteoporosis, which may be related to factors such as study design, sample selection, and individual differences.