Abstract: In this paper,the thermodynamics of carbon thermal reduction process of titanium-containing slag was analyzed.The results show that during the carbon thermal reduction process of titanium-containing slag,TiO₂ is reduced to a series of low-valence titanium oxides.TiO₂ begins to transform into Ti₃O₅ at 1359K then it probably forms Ti₂O₃ and TiC_xO_y which are finally reduced to TiC.CaO,MgO and Al₂O₃ in the slag could not react with carbon,while Fe₂O₃,V₂O₅,MnO and SiO₂can be reduced by carbon with the preference of Fe₂O₃＞V₂O₅＞MnO＞SiO₂.TiC formed in the early stage could react with TiO₂ to generate low-valence titanium oxides such as Ti₃O₅.Solid CaTiO₃ cannot directly react with carbon but the molten CaTiO₃ is reduced to TiC by carbon.The thermodynamic calculations provide important references for understanding transformation of minerals in titanium-containing slag during carbon thermal reduction process.