The invention provides a method for improving copper oxidation resistance of an authigenic nonmetal oxide composite film. Trace of Si elements are added into Cu so that a Cu@SiO2 composite attachmentfilm can be formed on the surface of Cu, and high-temperature oxidation resistance of the metal Cu and a product of the metal Cu is improved. By means of the method, trace of Si is mixed with Cu, repeated smelting is conducted in a vacuum smelting furnace, and a light doped CuSi alloy is manufactured. The added trace of Si elements are annealed in the Ar-20%H2 atmosphere, the trace of Si in the alloy is segregated to the surface of the alloy through the segregation effect and is reacted with residual O2 in the annealing atmosphere to generate SiO2, and therefore the Cu@SiO2 composite attachment film with a high melting point and stable performance can be formed, and it is ensured that a Cu metal matrix of the CuSi alloy is not oxidized under the high-temperature and pure-oxygen condition.By means of the method, the use reliability of copper-based parts and equipment is ensured, the cost is reduced, and industrial waste is reduced.