Abstract: A carbon free precast block was developed by using fused high-Al corundum as aggregate and electro-melting magnesia and ultra-fine Al2O3 and SiO2 powders as matrix materials. A small linear shrinkage of the precast block was found through the volume expansion due to the spinel which was produced from the reaction of MgO with Al2O3 in matrix. The precast block shows lower apparent porosity and higher hot modulus of rupture and slag corrosion resistance in comparison to conventional Al2O3-MgO-C brick. Practical applications revealed that bonding the precast blocks together as ladle lining can provide better thermal insulation which will effectively reduce the temperature drop of molten steel in refining process and prevent molten steel from carburization. The carbon-free precast block is thus regarded as a new type of ladle lining material that is beneficial to the production of low-carbon and ultra-low-carbon steel.