Abstract: The MCrAlY coatings were prepared by plasma spraying on TiAl alloy surface, laser remelting experiment had been carried out and the hot corrosion resistance of TiAl alloy, plasma-sprayed and laser-remelted MCrAlY coatings in 5%Na₂SO₄+25% NaCl(mass fraction) molten salt at 850℃ were researched. The hot corrosion failure mechanisms of three kinds of materials were analyzed and the influence of laser remelting on hot corrosion behavior of plasma-sprayed MCrAlY coating were discussed. The results show that the plasma-spayed MCrAlY coating has better oxidation resistance than the original TiAl alloy, and the laser-remelted coating has the best oxidation resistance. The hot corrosion of MCrAlY coating included surface oxidation and internal sulfide, and produced Al₂O₃, Cr₂O₃, NiO, NiCr₂O₄, Ni₃S₂ and CrS et al.