The new class of organic compounds – polyethylenepolyaminethiocarbamides, hexamethylenediaminothiocarbamides and their nitrile derivatives as inhibitors of steel corrosion in 5n in the hydrochloric acid has been investigated. It established that inhibitors for 40-60 min effectively protect steel against corrosion. On the expiry of indicated period corrosion process is activated. An increase of medium temperature (40-60°C) intensifies an effectiveness of action of inhibitors due to chemosorption of molecules of compounds on the surface of steel and formation of protective film.