The invention discloses a preparation process of a light electronic packaging material which consists of aluminum and silicon, wherein the content of silicon in mass percent is 30-80% and the balance is aluminum. The process comprises the steps of: mixing the aluminum and the silicon and then placing the mixture in a vacuum induction furnace for smelting at a temperature of 800-1300 DEG C so as to obtain a consumable electrode bar; loading in an electric slag furnace for electric slag smelting, wherein the work voltage of the electric slag furnace is 20-40V, the work current is 1-10kA, the arc strike block is a pure aluminum block and the arc strike slag is CaF2; adding electric slag which is thermally insulated for 4-8h at a temperature within 500-800 DEG C in the smelting process, wherein the addition of the electric slag is 3-4% of the quality of the consumable electrode bar and the electric slag consists of 20-30% of Na3A1F6, 25-35% of NaC1 and 45-55% of KC1 in mass percent; and annealing the aluminum-silicon cast ingot which is rapidly solidified by a water cooling crystallizer for 3-5h at a temperature within 325-375 DEG C after the smelting of the electric slag.