To provide a gravity casting apparatus, wherein occurrence of pin-holes in a light alloy casting can be restrained at the step of solidification of molten light alloy by pressurizing the whole molten light alloy before pouring the molten light alloy into a mold and until the solidification of the molten light alloy.

This gravity casting apparatus is provided with: a ladle 1 for pouring the molten light alloy into the mold; a ladle chamber 5 surrounding the lower portion from almost the upper surface of the ladle and having the opening hole at the upper end part; a mold chamber 9 which is arranged to be adjacent to the ladle chamber at prescribed intervals, and in which the mold is fitted superimposably onto the upper surface of the ladle chamber by turning over by 180; a sealing means 3 for sealing the opening hole of the piling-up position of the mold chamber and the ladle chamber; a swing-driving means 11 which allows the mold chamber to swing-shift to normal and reverse directions by 180 and to be superimposed on the ladle chamber by turning over the mold chamber by 180; a clamping means 12 for clamping the ladle chamber/the mold chamber in a superimposed state; and a pressurized gas supplying member 13 for supplying the pressurized gas into the airtight space demarcated with the ladle chamber and the mold chamber by communicatively connecting with the mold chamber.