Low cement Al2O3-SiO2 castables was prepared nsing super grade bauxite ( w( Al2O3) >85%) as ag-gregate, brown fused corundum, silicon carbide, Secar 71 CA cement, α-Al2O3 micropowder and micro-silica as fine powders. The influence of SiC (0, 5 wt%, 10 wt%, and 15 wt% ) on resistance to PbO-rich slag was investigated by static crucible slag test (1 300 ℃ for 5 h, in air). The slag corrosion mecha-nism of the castables was analyzed by means of SEM, EDS and XRD. The results show that the resistance of Al2O3-SiO2 castables to PbO-rich slag is improved ob-viously by the addition of SiC. The corrosion mechanism of the PbO-rich slag can be discribed as that PbO in the slag reacts with SiO2 and CaO in Al2O3-SiO2 castables, forming low-melting compounds (such as PbO ·SiO2 and 2 PbO·SiO2).