The invention relates to a method for smelting pure copper or high-content copper alloy materials, belonging to the field of metal metallurgy. The method comprises copper raw material pretreatment, smelting and deoxidation steps, wherein the copper raw material is pure copper with a copper content above 99.995 percent or a high-content copper alloy with a copper content no less than 90 percent. The copper bar is decontaminated and preheated to 500-600 DEG C and then fed into a smelting furnace. Shield gas atmospheres against oxidation are formed on the surface of copper raw material from the beginning of the smelting process of pure copper or high-content copper alloy. The shield gas is one or more gases selected from the group including N2, H2, CO and C2H2 or an inert gas such as Ar gas; and can inhibit the oxidation of molten liquid of pure copper or high-content copper alloy. The inlet of the mixed gas is 0.2-1.01 per minute. The smelting process is stopped at 1150-1200 DEG C after the copper bar is melted. The invention can efficiently prevent the oxidation of molten liquid during the smelting process, improve the fluidity, inhibit the reduction of cast product quality due to oxide interference, and increase the purity of molten liquid and the rate of qualified products.