The CALPHAD thermodynamic database is widely used for the complex thermodynamic equilibrium calculations and phase diagram calculations. Therefore, thermodynamic database becomes one of the most important tools for the materials design and process optimization in various materials science and engineering fields. In the present study, the experimental phase diagram study and thermodynamic modelling of ceramic materials will be briefly introduced. Then, our recent expansion of the thermodynamic database for refractories and high temperature ceramics will be presented, and several application examples for the corrosion of refractories and the degradation of high temperature ceramics be demonstrated.