The wide spread of osteoporosis in women in the post-menopausal period stipulates the need for new effective means of prevention and correction of pathologic alterations in the bone tissue. Effect of two peptide bioregulators: cartilages preparation based on the cartilaginous tissue extract and T-31 substance on the mineral density of rat bone tissue has been studied in the experimental model of osteoporosis. The study has revealed an osteoprotective effect of both studied substances, with significantly higher efficacy of the preparation based on cartilaginous tissue extract. The substances exerted both prophylactic effect on the status of the cartilaginous tissue, preventing the decrease of mineral density of the bone tissue in rats after ovariectomy, and corrective effect by increasing the bone tissue density, which was reduced as a result of ovariectomy.