A loadlock apparatus includes a loadlock chamber including a first opening and a second opening separated in a vertical direction; a first slit valve including a first valve plate configured to move between a first open position where the first opening is open and a first closed position where the first opening is closed, the first open position being a position moved downward from the first closed position; and a second slit valve including a second valve plate configured to move between a second open position where the second opening is open and a second closed position where the second opening is closed, the second open position being a position moved upward from the second closed position.