The study presents the role of thymosin β, particularly thymosin β4, its sulfoxide and the degradation product- peptide Ac-N-acetyl-aspartyl-serine-lysine-proline in the processes of formation and regeneration of blood vessels with particular emphasis on the coronary vessels and capillaries. It is presented the relationship between disease such as atherosclerosis and the thymosin β. Interesting is the variety of mechanisms in which the thymosins are involved, among other regulating the mobility of the cells by interacting with actin, modulation of expression of growth factors, matrix metalloproteinases and other proteins. In this way, thymosin β affects proliferation, migration, apoptosis, and the formation of inflammation and scarring. The article describes also the the diagnostic and therapeutic potential of thymosin β in the treatment of cardiovascular diseases.