The present invention relates to a method for improving the performance of P-type ohmic contact of gallium nitride LED wafer. Magneto sputtering is used to spray nickel material in nano particles onto the surface of gallium nitride epitaxial layer. The thickness of nickel is between 1 nm to 100 nm. Following that, at least one layer of high work function metal film is deposited onto the surface of the nickel metal layer, and the ratio of the thickness of the nickel metal layer to that of high work function metal film is 1:0.5.about.4. Zinc oxide may replace nickel metal layer and high work function metal film. The object of the present invention is to simultaneously reduce the contact impedance of P-type luminous zone and enhance the traverse of electric current, thereby attaining an eventual equilibrium of contact impedance and luminous efficiency and thus increasing the life span of the wafer. The present invention prescribes the thickness ratio for each contact metal layer, the conditions of thermal treatment and the unique design patterns for electrodes. Experiments prove that the present invention is able to control the decay of light intensity of gallium nitride LED in 1000 hours to less than 10% with good thermal stability and contact impedance being reduced to 2E-6 .OMEGA.-cm.sup.2.