Abstract <p>The review is devoted to the feasibility of using flavonoids in the complex therapy of osteoporosis. The numerous types of pharmacological activity of these polyphenolic compounds of plant origin, including anti-inflammatory, antioxidant, antiproliferative, immunomodulatory, antitumor, anticoagulant, and others, have led to a careful approach to the possibility of their clinical effectiveness in bone pathology. Experimental studies in recent years have established that the protective effect of flavonoids, which prevents pathological bone loss, is primarily due to the activation of the formation of new bone tissue by stimulating the proliferation and differentiation of osteoblasts, as well as weakening the process of bone resorption due to the inhibition of osteoclastogenesis. Possible mechanisms of the observed effects are discussed, considering the impact on intracellular signaling processes. A positive effect of the estrogen-like properties of several flavonoids on the process of osteogenesis is noted. The promising properties of the most widely used flavonols, flavones, flavanones, flavan-3-ols (catechins), anthocyanidins, and isoflavones are discussed, allowing optimistically consider their future clinical use. As many authors believe, further in-depth preclinical studies should answer many remaining questions regarding the mechanisms of action of flavonoids, as well as resolve the issue of their bioavailability.</p>