The Mullite lightweight brick is made of mullite and other fine raw refractory materials with advanced techniques. It is a kind of new popular energy-saving material widely used in metallurgy, ceramics, glass and chemical industry as high temperature liner, such as in pyrolyzers, chemical industry furnace, metallurgy industry furnace, anneal furnace, heating furnace, electric resistance furnace, roller kiln, tunnel kiln and shuttle kiln.