Normobaric hypoxic therapy is a therapeutic or prophylactic use of gas hypoxic mixture containing 10% oxygen and 90% nitrogen, alternating with breathing atmospheric air at normal barometric pressure. The use of normobaric hypoxic therapy allows activating and using genetically programmed mechanisms aimed at increasing the nonspecific resistance of the body. The history data, pathogenesis of normobaric hypoxic therapy, the procedure and its effect on the cardiovascular system are described.