Introduction. Numerous studies show a strong link between metabolic syndrome (MetS) and osteoarthritis (OA). MetS aggravates and reinforces systemic inflammation, which in turn leads to the progression of OA. This reduces physical activity and worsens the quality of life of elderly patients. The red blood system plays an important role in assessing pathological changes in the body. MetS is a systemic disorder. For this reason, it is possible to study red blood as an object expressing metabolic disorders in all organs and tissues. While these alterations of the red blood system as part of metabolic disorders have not been studied enough, we can talk about incomplete and not always adequate correction of metabolic shifts. New approaches and innovative programs in diagnostics and prevention are needed. Objective. The aim of our research was to study the functional activity and mechanisms of red blood regeneration in elderly to obtain new data characterizing the cohort of elderly patients with MetS and OA. Methods. The assessment of hematological parameters and parameters of erythrocyte balance was used. 80 people participated in the study. 40 elderly patients with MetS OA: 22 men (62,5±4,44 age) and 18 women (66,33±8,07 age). The control group consisted of 40 elderly people: 23 men (60,96±1,74 age) and 17 women (60,53±2,0 age). Results. The daily production of red blood cells in the group of women with MetS and OA was significantly reduced by 30% compared to the control group. In elderly patients with MetS and OA (both man and women), immature reticulocytes appear, which indicates increased regeneration of the red blood system in conditions of tissue hypoxia against the background of hyperglycemia. In women with MetS and OA, mean corpuscular volume (MCV) was significantly increased compared to the control group as a compensatory and adaptive response to an increased need for hemoglobin. Conclusion. MetS is important both from a medical and social point of view. MetS in combination with OA inevitably contributes to a decrease in the quality and life expectancy of elderly patients. In the course of the study, the peculiarities alterations of the red blood system in elderly patients with MetS and OA were revealed. This data provides the basis for further research in this matter and may lead to new opportunities for therapeutic intervention.