Thiamine belongs to water soluble group of vitamins. In medicine thiamine is used as thiamine hydrochloridum, thiamine nitrate, thiamine pyrophosphate and as synthetic derivatives soluble in fat like sulbutiamine and benfotiamine. Thiamine and its derivatives take a part in many important biological processes among in growth and development of a organism. Its have roles in proper functioning of circulatory and nervous systems. Thiamine is necessary to oxydizing at carbohydrates and in producing of energy especially for functioning nervous system, cardiac muscle and skeletal muscles. In this work the properties of thiamine and its biological activity were described. The pharmaceuticals and dietary supplements with thiamine were presented.