In steelmaking process, the corrosion of refractory materials shortens the life of refractory, resulting in a long-term shutdown due to frequent refractory replacements. Thermodynamic assessments to such phenomena have been studied allowing deeper understanding of the corrosion process. In order to kinetically understand such phenomena for the industrial purpose, however, a model calculating the dissolution behavior of refractory in slags is highly necessary. We are currently developing software to calculate multicomponent ionic diffusion in oxide melts and dissolution rate of oxide particles in slags. In addition, interdiffusion coefficient database for molten oxide melts is under construction based on classical diffusion couple experiments.