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7% yttria stabilized zirconia (7YSZ) thermal barrier coatings (TBCs) prepared by air plasma spray were laser-remelted, and subsequently pre-heated and Al2O3 sol-gel repaired for restraining the crack growth in the remelted coatings. The as-prepared coatings were exposed to high temperature molten CaO-MgO-Al2O3-SiO2 (CMAS) to explore their corrosion resistance. The results show that both the laser remelted and the pre-heated, the laser-remelted coatings are densified by CMAS attack. In addition, the thickness of the densified layers is on the same order of that of the non-remelted coatings. Despite of this, the densified layer in the laser remelted coating repaired by Al2O3 sol-gel is much thinner than the other coatings. This indicates that Al2O3 sol-gel repairing coupling with laser-remelted method can effectively improve the CMAS resistance of 7YSZ TBCs due to the refractory anorthite generated during corrosion process. This refractory compound produced between CMAS and Al2O3 sol-gel is capable to decrease the mobility and corrosivity of the CMAS.