Using thermodynamic data determined in present study, a stability diagram for Al 2 O 3 , Ti 2 O 3 and Ti 3 O 5 phases was constructed as a function of dissolved aluminum, titanium and oxygen contents in liquid iron. The result indicated that at equilibrium condition titanium oxides would not form on titanium addition in Al-killed liquid steels with soluble aluminum content of 0.02-0.05 mass% at 1 873 K.