A surface treatment method of a copper foil, an antioxidant copper foil, and a cathode of a lithium battery are provided. The antioxidant copper foil includes a copper foil substrate and an antioxidant layer formed thereon. The antioxidant layer contains chromium elements derived from a chromic acid compound, and contains nitrogen elements at least partially derived from an aminotetrazole compound and a nitrogen-containing heterocyclic compound. The antioxidant copper foil satisfies the following characteristics: (a) the antioxidant layer has a chromium content of between 5 and 35 μg/m2 determined by XRF; (b) the antioxidant layer has a nitrogen content of between 0.1 and 10 wt % determined by XPS; (c) the antioxidant copper foil has a C—N signal detected by headspace GC-MS; and (d) after baking the antioxidant copper foil at 250° C. for 10 minutes, a surface color difference ΔE of the antioxidant layer is not greater than 8.