Ferric and cupric ions are effective inhibitors for the corrosion of titanium in boiling 10 per cent sulfuric and boiling 10 per cent hydrochloric acids. The corrosion rates range from 3 to 55 mdd (0.001 to 0.012 ipy) for inhibitor concentrations from 0.03 to 0.005 M. Although the inhibitors are consumed as titanium corrodes, the consumption is moderate, particularly at the higher inhibitor concentrations corresponding to low corrosion rates. The primary mechanism, as indicated by potential measurements, is proposed as occurring through adsorption of Fe +++ or Cu ++ on the metal surface with accompanying satisfaction of surface valences and formation of a dipole layer with negative charge outward accounting for a noble potential.