The invention discloses a method for evaporating and plating a graphite phase CN film. The method comprises the following steps that a, a monocrystalline silicon wafer is used as a substrate, the substrate is cleaned, and stains on the surface of the substrate are removed; b, the substrate is placed in an evaporation coating chamber, carbon nitride powder with the purity of 99.99% as an evaporation source, and the CN film is evaporated and plated on the surface of the substrate; and c, the substrate plated with the CN film is put into an annealing furnace, and carries out vacuum annealing at the temperature of 400 DEG C-600 DEG C for 3 hours, and then the substrate is naturally cooled to normal temperature to obtain the graphite phase CN thin film. The method directly obtains the high-purity CN film by evaporation deposition, the uniformity of the film is good, and the film quality can be improved.