The effects of 3%-5% rhenium addition (mass fraction, similarly hereinafter) on the high-temperature corrosion resistance of CoNiCrAlY alloys were evaluated at 1000 ℃ by means of XRD, SEM and EDS. It is shown that there is an internal oxidation whether the rhenium is added to the alloy or not. The addition of rhenium can reduce the thickness of Al-depletion zone, stabilize the α-Cr(Re) phase and benefit the formation of Cr2O3 oxide scale which separates the base material from the molten salt and prevents from high-temperature corrosion