An evaporator including a housing with a refrigerant inlet and a refrigerant outlet; heat transfer tubes contained in the housing, in which chilled water for heat exchange with refrigerant inside of the housing flows; at least one distribution tray placed apart from the heat transfer tubes and having a plurality of holes for distributing refrigerant over the underlying heat transfer tubes; a vapor-liquid separator that is placed above the distribution tray and separates an introduced mixed refrigerant into vapor refrigerant and liquid refrigerant and distributes the liquid refrigerant to the distribution tray; and at least one tube support with a plurality of holes for passing the heat transfer tubes through, that is placed inside of the housing and supports the distribution tray.