Disclosed is a surface treating agent for
metallic materials that has various properties such as
corrosion resistance and overcoating properties and, when used in
coating-type surface treatment, particularly can form a film , which has excellent adhesion to the surface of
metallic materials, and can fix, within the film, a component capable of functioning as a
corrosion inhibitor for
metallic materials. The surface treating agent for metallic materials comprises a
silicic acid compound (A), an organoalkoxysilane (B), a metallic compound (C) containing at least one
metal element selected from the group consisting of Zr, Ti, Co, Fe, V, Ce, Mo, Mn, Mg, Al, Ni, Ca, W, Nb, Cr, and Zn, at least one compound (D) selected from the group consisting of
phosphoric acid compounds and fluoro compounds, water (E), and an
alcohol (F) produced upon
hydrolysis of the organoalkoxysilan (B). The
molar concentration (mol / L) of the
alcohol (F) in the treating agent has been regulated in a predetermined range.