Abstract: The relation between preparing parameters of magnesia-zirconia bricks and their resistance to RH slag corrosion was studied by contrasting the slag resistance behaviors of magnesia-zirconia bricks and magnesia-chromite bricks and by a simplified model. The preparing parameters that influence the RH slag resistance properties of magnesia-zirconia bricks, such as grain mixture ratio, agglutinant, sintering temperature, zirconia content, and variety of zirconia, were analyzed by orthogonal experimental design (OED). The results indicate that sintering temperature and zirconia content are two key influencing factors. The effects of sintering temperature and zirconia content on the ratio of infiltrate depth were further examined by the steepest ascent method and central composition design (CCD), and a statistic analysis model of resistance corrosion of magnesia-zirconia bricks eroded by RH slag was built.