An evacuation system in an ultra-high vacuum sputtering apparatus capable of shortening the pumping time of the system. A main pump, composed of a turbo-molecular pump and a baffle is positioned upstream of a main pump and cooled to a temperature in which argon gas is not absorbed and only water is absorbed. The pump and a vacuum chamber are separated by a valve. A pipeline circulates a heating medium to rapidly heat and cool the vacuum chamber for enabling a gas discharge from the vacuum chamber whereby the pumping time can be reduced and the overall production of the system can be increased.