These materials in architecturally glass or metal have weaknesses such as inadequate insulating quality, combustibility and toxic gases in fires substance. However, Autoclaved Lightweight Concrete(ALC) has excellent thermal insulation properties and seem to possess the superb insulating quality as substitute of existing exterior materials. This research is to compare experimentally to the kind of the strength properties of ALC materials which mixed with blast furnace slag pounder and silica fume. For the purpose of increasing the strength, the plastic states of ALC evaluate the physical characteristics as microstructure and strength according to various specific gravity. According to the quicklime quantity the compressive strength is proportionate depend on the absolute dried specific gravity. When not putting in 10% quicklime, the compressive strength appeared most lowly with 14.0MPa. When putting in the quicklime, the strength appeared higher with 15.1MPa. And strength of specimen containing 2.25% silica fume is 15.6MPa increased 10.3% than reference specimen 14.0MPa.