PURPOSE: A vacuum melting apparatus and method for light metal are provided to produce an ultra-pure casting product of light metal material by discharging the gas produced in melting the light metal nearly completely from the molten metal. CONSTITUTION: A vacuum melting apparatus for light metal comprises a vacuum melting chamber(100) which includes a material inlet part(20) and a molten metal guide pipe(14), a molten metal insulation furnace(10) which moves up and down inside of the vacuum melting chamber and is equipped with a molten metal outlet pipe(16) on the bottom thereof and a first heater(17) on the exterior thereof, a valve rod(12) which opens and closes the molten metal outlet pipe, and a pipe melting furnace(21) which is connected to the material inlet part on one side and located above the molten metal insulation furnace on the other and is equipped with a second heater(27) on the exterior thereof.