The oxidation behavior of CuNi, CuFeNi, CrCu_0.3FeNi, and Al_0.4CrCuFeNi₂ Co-free Cu-containing concentrated solid solution alloys was investigated in steam conditions under 500, 600, and 700°C for 25 h. All the alloys have a face-centered cubic structure. The kinetic curves of oxidation were measured, and the microstructure and elemental distribution of oxide scales were analyzed. The oxidation of all the Cu-containing alloys indicated parabolic behavior, and those appeared to have better corrosion resistance than normal 316 SS. The parabolic rate constant increased with increasing temperature. The oxidation resistance of CuNi and CuFeNi were relatively poor due to the formation of unprotective NiO and Fe₃O₄ oxide scales, which were thicker than that of CrCu_0.3FeNi and Al_0.4CrCuFeNi₂ at all testing temperatures. Cross-sectional electron probe microanalysis (EPMA) and X-ray diffraction (XRD) results revealed that, by the addition of Cr and Al, CrCu_0.3FeNi and Al_0.4CrCuFeNi₂ had the enhanced oxidation resistance, which is probably due to the formation of Cr₂O₃ and Al₂O₃ inner oxide layer.