Abstract: Yttria-stabilized zirconia with doping different content of Dy₂O₃ (DYSZ) was prepared by solid state sintering method. The phase stability and molten salt corrosion behavior of DYSZ were characterized by XRD and SEM techniques. Results showed that some new diffraction peaks ascribed to monoclinic phase appeared in the YSZ with doping 6% of Dy₂O₃ after annealing at 1500 ℃ for 24 h. The phase stability of the samples improved with the increase of Dy₂O₃content. During the hydrothermal degradation, the DYSZ materials had better phase stability than the 8YSZ material.Under molten salt corrosion conditions, V₂O₅ preferentially reacted with Dy₂O₃ to form DyVO₄, leading to cubic/tetragonal to monoclinic.Phase transformation stress, formation and irregular growth of the resultant DyVO₄ crystals could accelerate the material degradation.