The invention discloses an anti-oxidation metal surface treating agent. The anti-oxidation metal surface treating agent is prepared from, by weight, 0.4-0.5 part of borax, 40-50 parts of polyvinyl alcohol, 12-15 parts of polyethylene glycol, 0.4-0.6 part of emulsifier op10, 0.3-0.5 part of glycerol, 0.6-0.8 part of triethanolamine, 6-8 parts of benzotriazole, 6-7 parts of sodium benzoate, 2-3 parts of sodium dodecyl sulfate, 0.4-0.6 part of butanedial, 4-5 parts of nano-crystalline cellulose, 0.3-0.4 part of diethylenetriamine, 0.32-0.4 part of vinyl trimethoxy silane, 0.2-0.3 part of polyvinylpyrrolidone, 1.2-1.6 parts of copper powder, 0.8-1.2 parts of catechin, 0.4-0.6 part of edetate disodium and a proper amount of deionized water. The prepared metal surface treating agent has the advantages that a preparation method is simple, cost is low, film forming performance is good, after-treatment is easy, the surface treating agent has good anti-oxidation, anti-rust and anti-corrosion functions on a metal surface, the effect is good, and application prospects are good.