Ni-Cr-Al-Fe based alloys with different Al content were prepared by fusion casting. The effects of Al content and pre-oxidation treatment on oxidation behavior of the Ni-Cr-Al-Fe based alloy were investigated. The morphology and chemical composition of the oxide films were characterized by FE-SEM (EDS) and XRD, respectively. The results show that the oxidized kinetic curves of the Ni-Cr-Al-Fe based alloys at 600°C follow the parabolic rule. Both of the increase of Al content and pre-oxidation treatment can enhance the oxidation resistance of the alloy. The compositions of the oxide films after pre-oxidation at 1000°C and oxidation at 600°C are closely related to the Al content. Higher Al content is helpful to the formation of single Al 2O 3 structure, which is beneficial to the oxidation resistance of the alloy. With further oxidation, complex oxide or spinel-type oxide may be formed at the local region of the surface. The oxidation of the matrix of the Ni-Cr-Al-Fe based alloy can be effectively prevented after the pre-oxidation treatment. Stable oxide phase diagram of ternary Ni-Cr-Al alloys at 600°C is also calculated by Wagner's critical theoretics.