In order to enhance the high‐temperature oxidation resistance properties of Inconel 617 alloy, NiCoCrAlY and NiCoCrAlY CeO₂ composite powder coatings metallurgically bonded to substrate were prepared on the surface of Inconel 617 alloy by electron beam cladding. The effect of rare earth oxide CeO₂ on the oxidation resistance of NiCoCrAlY coating was investigated. The isothermal oxidation behavior of the substrate and NiCoCrAlY cladding layer with different CeO₂ contents (1%, 2%, 3%, and 4%) and without CeO₂ oxidized at 1050°C for 20 h, 40 h, 60 h, and 100 h was analyzed. The microstructure and phase composition of the coating after electron beam treatment were tested. The results show that the self‐repair of Al₂O₃ and Cr₂O₃ oxide film can be improved under a high‐temperature oxidation environment with the addition of CeO₂, and the oxidation resistance of NiCoCrAlY coating can be effectively strengthened by adding CeO₂. The improvement effect is most obvious when the content of CeO₂ is 2%.