The hot corrosion behavior of the La2(Zr0.7Ce0.3)2O7 ceramic with a pyrochlore structure was evaluated at selected temperatures of 800, 900 and 1000 °C. The phase constituents and microstructure of the corroded La2(Zr0.7Ce0.3)2O7 ceramic were investigated by X-ray diffraction, scanning electron microscopy and energy dispersive spectrometry. The main corrosion products on the surface of the La2(Zr0.7Ce0.3)2O7 ceramic in V2O5 were (La,Ce)VO4 and m-ZrO2 at 800, 900 and 1000 °C, and the corrosion-layer thickness decreased whereas the size of the corrosion products increased gradually as the corrosion temperature increased. For the Na2SO4+V2O5 salt mixture, the main corrosion products were mainly (La,Ce)VO4 and t-ZrO2 at 800, 900 and 1000 °C on the surface of the La2(Zr0.7Ce0.3)2O7 ceramic; Na2SO4 may have remained on the ceramic surface after corrosion at 800 °C and reacted completely with the increase of the corrosion temperature. The chemical reactions between the La2(Zr0.7Ce0.3)2O7 ceramic and molten V2O5 or Na2SO4+V2O5 salt mixture are the primary corrosion mechanisms for the degradation of the La2(Zr0.7Ce0.3)2O7 ceramic. The lower concentration of V2O5 in the Na2SO4+V2O5 salt mixture compared to the case of V2O5 corrosion alone is significantly responsible for the development of t-ZrO2.