An improved generalized self-consistent scheme (GSCS), which has a simplified computation process, was proposed to predict the properties, based on microstructure, of multiphase materials. The results of the prediction of the elastic modulus, Poisson's ratio, coefficient of thermal expansion, and coefficient of thermal conductivity of an Al 2 O 3 -C refractory using a multiscale homogenization method with this improved GSCS agree with the experimental results. It is found that understanding the microstructure and choosing a suitable matrix for the prediction are very important for prediction accuracy.