The invention relates to castable, in particular to castable for ladle linings or working layers. In order to solve the technical problem, the castable is provided to be used for a direct lining, making contact with molten steel, of a steel ladle. The castable is prepared from, by weight, 8%-20% of sub-white corundum ranging from 12 mm to 8 mm, 11%-15% of sintered porous alumina spinel ranging from 8 mm to 5 mm, 12%-15% of sintered porous alumina spinel ranging from 5 mm to 3 mm, 10%-15% of sintered porous alumina spinel ranging from 3 mm to 1 mm, 30%-35% of sintered porous alumina spinel smaller than or equal to 1 mm, 0-5% of modified dead burned high-calcium magnesite smaller than or equal to 1 mm, 1% of tri-chromium dicarbide powder, 3%-5% of compound gel powder, 1% of hydrated alumina micro powder, 1% of nacrite powder, 0.5% of bismuth germanate powder, 3%-5% of modified pure calcium aluminate cement, 0.1% of C7H10N2O2S, 0.1% of C21H14Na2O6S2 and 0.05% of 2-morpholineethanesulfonic acid. According to the castable, the reaction degree of the steel ladle lining material and slag can be reduced, high-temperature performance and slag corrosion resistance of a ladle product with slag resistance are improved, thermal shock resistance of the ladle is greatly improved, the service life of an integrally poured ladle is effectively prolonged, and the service life is prolonged by 30% or above compared with ordinary same types of ladles.