A semiconductor manufacturing apparatus includes a loadlock module including a loadlock chamber in which a substrate container is received, wherein the loadlock module is configured to switch an internal pressure of the loadlock chamber between atmospheric pressure and a vacuum; and a transfer module configured to transfer a substrate between the substrate container received in the loadlock chamber and a process module for performing a semiconductor manufacturing process on the substrate, wherein the loadlock module includes a purge gas supply unit configured to supply a purge gas into the substrate container through a gas supply line connected to the substrate container; and an exhaust unit configured to discharge a gas in the substrate container through an exhaust line connected to the substrate container.