The review of modern literature presents data on the prevalence of obesity and osteoporosis in Ukraine and the world. These diseases are associated with severe and persistent symptoms, slow recovery, and a significant negative impact on patients’ quality of life. Melatonin is a hormone with enormous biological functions. As a widely available and versatile molecule in vivo, it has powerful antioxidant and anti-inflammatory properties in various bone diseases, has an effect on the restoration of damaged tissues, helps to reduce the amount of visceral adipose tissue and improves eating behavior. However, the informational analysis of the problem showed that there are still many unsolved questions regarding the optimal dosage and timing of melatonin administration, as well as the study of any possible side effects during its longterm administration. At the same time, the study of the effect of melatonin on the state of the bone system in obesity can contribute to a deeper understanding of the pathogenesis of both osteopenic and metabolic syndromes for the development of new methods of treatment and prevention.