the corrosion behavior of cobalt-based alloy powder with different Te content that was sintered under non-vacuum environment is researched high temperature molten salt in a static 800±5℃75% Na2SO4+25% NaCl high temperature molten salt. Making use of OM, SEM and XRD diffraction analyze the alloy microstructure, corrosion product morphology and phase composition, and the results show that: with the increase of Te mass fraction in cobalt-based alloy, high-temperature molten salt corrosion rate decreased gradually; when the Te content is about 1.6wt%, the alloy substrate surface form a kind of homogeneous and dense Cr2O3 protection oxide film and the new phase (CoTeO3, Fe2TeO5) dispersed in the matrix to inhibit Co atoms diffusing to grain boundaries, which retard alloy matrix element dissolution and improve the performance of the alloy hot corrosion. Corrosion rate of cobalt-based alloy decreases from free Te 4.0483mg/(cm2*h) to 0.216mg/(cm2*h).