Anatase TiO2 is a promising corrosion resistance material due to the excellent corrosion resistance, order array structure and good adsorption stability. However, the fundamental mechanism of interaction between TiO2 and sulfur (S) is unclear. In particular, the nature of corrosion resistance of alloy-doped TiO2 is not understood. By using the first-principles calculations, we study the sulfuretted mechanism of TiO2 and explore the influence of Ag and Au on the corrosion resistance of TiO2. The results show that sulfur is favorable to occupy the tetrahedral interstitial site because sulfur occupied this position can improve the localized hybridization between S-3p state and O-2p state, which forms the S-O bond. The calculated bond length of S-O bond is 1.967 angstrom. In particular, Ag dopant and Au dopant enhance the localized hybridization between sulfur and oxygen. The calculated bond length of S-O bond for Ag dopant (1.483 angstrom) and Au dopant (1.506 angstrom) is shorter than that of S-doped TiO2. As a result, those alloying elements improve the corrosion resistance of TiO2. Compared to Au dopant, Ag dopant improves the corrosion resistance of TiO2 because the bond strength of S-O bond for Ag dopant is stronger than that of Au dopant. (C) 2019 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.