The sintering performance of corundum-silicon nitride castable with brown corundum dust powder added was studied in this paper to provide a theoretical basis for the reuse of this waste powder. Waste powder, corundum, silicon nitride and silicon carbide were used as raw materials in this experiment. The sintered samples were measured routine physical property, and analyzed the microstructure of samples by SEM. Results shows that the addition of dusting powder could promote the sintering performance of non-oxides and the formation of Sialon, and improve the physical properties of samples. But when dusting powder added over 6% of the total, there are too much liquid phases, which will reduce the fire resistance performance at high temperature, so the appropriate added amount of dusting powder should be less than 6%.