Collagen is one of main structural protein in organism. It plays a fundamental role in a lot of functions crucial for proper functioning connective tissue. The metabolism of the protein-production, modification and degradation should be balanced, in other situation appear serious health consequences, inter alia course of the arteriosclerosis, which is one of the most serious contemporary medical problem in developed countries, might be deteriorated. The collagen is crucial for the atherosclerotic plaque stability, if there is the deficiency of it, the blood vessels are more prone to rupture. On the other hand, accumulation of the protein leads to the arterial stenosis. It is suggested that collagen is involved in the calcification of atherosclerotic areas of the arteries, in binding of low density lipoproteins, stimulation of migration and apoptosis of arterial smooth muscle cells.