High alumina castable is a refractory castable made of high alumina raw material with binder and aggregate in traditional ratio.On the basis of the preparation of high strength and high aluminum castable, the granule gradation is adjusted, different admixtures are added, cement dosage is reduced, performance is improved, medium temperature strength and softening temperature under load are increased, thermal conductivity is reduced, and thermal stability is good.The furnace body structure integrity is strong, the air tightness is better than the brick furnace, extends the furnace life, saves the furnace repair cost, the economic benefit is remarkable as the high aluminum refractory castable characteristic.