High-dispersed magnetized iron preparations of various coercive force and its preparations with Ag, Au, Pt obtained by thermochemical method have been studied for their effect on plants and bacteria pathogenic for animals. It is established that magnetized iron intensifies antibacterial effect of certain metals. Of the studied preparations only high-dispersed Fe-Ag had distinctly expressed bactericidal effect. Other preparations had weak antibacterial effect or had not it at all. All the preparations have strong adsorption capacity.