In recent years an increasing socioeconomic burden of two pressing problems has been observed: enormous prevalence of obesity and - along with aging of populations - great number of people affected with osteoporosis. Visceral obesity, expressed by increased waist circumference, is according to the latest guidelines a crucial component of metabolic syndrome (MS). So far the two entities have not been linked, as studies have proven beneficial effect of increased body weight on bone mineral density (BMD). It has been shown however, that adipose tissue is actually an endocrine tissue, secreting numerous biologically active substances that influence also bone. Moreover, an adipocyte and osteoblast derive from a common precursor cell. There is also increasing number of evidence showing common genetic determination of the diseases. Data from experimental and epidemiological studies proves that obesity itself as well as remaining components of MS might have negative influence on bone. BMD as well as fracture risk have been shown to be raised in patients diagnosed with MS. The same has been observed for high blood pressure. What’s more, contradiction between high BMD and - simultaneously - high fracture risk in subjects with type 2 diabetes has not been convincingly explained. The paper discusses reports and controversies on coexistence and interactions between MS and osteoporosis and its complications.