The anticorrosion properties of hexamethylenetetramine, boric acid, and a mixture of individual polyethylene polyamines have been investigated, as well as the dependence of steel corrosion rate in inhibited hydrochloric acid on the molar ratio of the components, reaction temperature, and synthesis time. The optimal molar ratios of boric acid, polyethylene polyamines, and hexamethylenetetramine and synthesis time and temperature have been determined. It has been shown that boric acid can be used as a component of the active base of a corrosion inhibitor. The use of boric acid is due to the synergistic effect of the test components of the active base and a low cost and nonhazardous nature of the material.