Biochanin A is a naturally occurring isoflavone. Its main sources are clover species such as Trifolium pretense, Trifolium subterraneum or Trifolium incarnatum. Phytoestrogens, including isoflavones, are plant-derived substances, which exhibit estrogen-like properties, thus they may be used as an alternative for hormonal replacement therapies and prevent postmenopausal osteoporosis. Therefore, the aim of the presented study, was to investigate the effect of biochanin A on chemistry and mechanical properties of skeletal system in rats with ovariectomy-induced osteoporosis. The animals were divided into 4 groups--(I) sham-operated rats, (II) ovariectomized rats, (III) ovariectomized rats receiving estradiol at a dose of 0.2 mg/kg p.o., which were a positive control, and (IV) ovariectomized rats receiving biochanin A at a dose of 5 mg/kg p.o. for four weeks. The administered dose of biochanin A is considered as moderate for human, which can be received in the dietary supplements, and was established using ten-fold conversion rate resulting from faster metabolism in rats. Obtained results showed that ovariectomy induced harmful changes in bone tissue, causing worsening in both chemistry and mechanical parameters in bones. Administration of biochanin A to ovariectomized rats did not affect any changes in bone tissue in comparison to the bones of untreated ovariectomized rats. There was neither improvement nor deterioration noted in chemical composition and mechanical properties in all analyzed bones. Basing on the results, it could be concluded, that biochanin A administered in a moderate dose shows no influence on bone tissue of rats with ovariectomy-induced osteoporosis.