The invention discloses a method for preparing a noble metal nano-crystal load copper-zinc-tin-sulfur film. The method comprises the steps of preparing a noble metal nano-crystal particle dispersion liquid, preparing a dispersion liquid containing copper, zinc, tin, and sulfur sources, mixing the two dispersion liquids in the presence of stabilizer into a precursor solution with good dispersity and stability, and preparing a noble metal nano-crystal load copper-zinc-tin-sulfur film through spin-coating and sintering processes. According to the preparation method, the operation is simple, the reaction conditions are mild, and the requirement on raw materials is low. A noble metal nano-crystal load copper-zinc-tin-sulfur film prepared by the method has an excellent catalytic effect, the load capacity of noble metal nano-crystal can be regulated arbitrarily, and the film can be widely used in different fields.