The invention provides a preparing method of a molybdenum or molybdenum alloy surface Pd-CeO2-Co nanometer coating. Molybdenum or molybdenum alloy is subjected to cleaning and surface etching, an even pitted surface is formed on the surface of the molybdenum or molybdenum alloy, and a molybdenum base body or a molybdenum alloy base body is prepared through flushing and drying; Pd(NO3), CeO2 and cobaltous acetate are dissolved in anhydrous isobutanol and heated to 60 DEG C to 70 DEG C, diethanol amine and distilled water are added, after ammonium hydroxide is added, the pH value of the solution is adjusted to 7.5-8, sol is formed through constant stirring, and after evaporation and condensation are carried out in 10-24 h, stable, even and transparent precursor sol is obtained; and the molybdenum base body or the molybdenum alloy base body is coated with the precursor soil, and the molybdenum or molybdenum alloy surface Pd-CeO2-Co nanometer coating is obtained. The nanometer Pd-CeO2-Co nanometer coating prepared through a roller painting method is even and high in density, superior anti-oxidation performance is achieved, and the high-temperature oxidation corrosion can be resisted. The using temperature of the molybdenum or molybdenum alloy processed through the surface coating can reach 1,500 DEG C.