To provide a cooling device capable of shortening a cooling time of a cooling stage.

This cooling device 1 comprises a liquid nitrogen tank 9 allowed to come into contact with and apart from a cooling stage 2 holding a specimen. The liquid nitrogen tank 6 comprises a pipe 11 connected to a bellows 7 through an insulated bar 8 and communicating with the hollow part of the bellows 7 to regulate the pressure of the bellows 7 and a three-way valve 10 installed in the pipe 11. One end of the three-way valve 10 is open to the atmosphere, and the other end is connected to a vacuum pump 9. Allowing the three-way valve 10 to communicate with the atmosphere brings the inside of the bellows 7 into the state of the atmosphere and brings the liquid nitrogen tank 6 into contact with the cooling stage 2. On the other hand, by switching the three-way valve 10 to the vacuum pump 9 side, the inside of the bellows 7 can be brought into a vacuum (low pressure) state, and the liquid nitrogen tank 6 can be moved apart from the cooling stage 2.