The invention discloses a proton exchange membrane fuel cell metal bipolar plate doped with a multilayer gradient membrane on the surface, and a preparation method of the proton exchange membrane fuel cell metal bipolar plate. The Ti, Al and/or Mo doped C/CrN multilayer gradient membrane is prepared on the surface of the metal bipolar plate by a closed-field unbalanced magnetron sputtering technology. The doped C/CrN multilayer gradient coating comprises a graphite-like carbon coating, a CrN coating and a Cr transition layer as well as Ti, Al, Mo, W, Nb, Ni, Zr, Fe, Si and other elements doped in the graphite-like membrane and/or the CrN coating for structure and component control. Compared with the prior art, the proton exchange membrane metal bipolar plate provided by the invention has the characteristics of excellent conductivity and corrosion resistance, low open porosity and cost and the like, the stacking performance of a fuel cell is greatly improved, and the service life of the fuel cell is greatly prolonged; and the metal bipolar plate can meet the use requirements of the fuel cell, and has broad application prospect.