Hydrophobization of a surface by fluorosilanes is proposed for protection of low-carbon steel with conversion coatings from atmospheric corrosion. The effect of the heterogeneity of conversion coatings on their hydrophobicity is shown. Employment of superhydrophobization processing increases the angle of wet- ting of the surface by a water droplet up to 160° and significantly enhances the anticorrosion properties of such a composite coating.