To provide an air shutter device that can be juxtaposed to a door device for opening/closing an opening, while reducing heat energy loss by satisfactorily intercepting the inflow of warm air from the outside of a refrigerator and the outflow of cold air from the inside of the refrigerator.

This closing device comprises the door device 1 for shielding the opening O serving for communication between a first space A and a second space B, and the air shutter device 5. Gas in the first space A is cold air lower in temperature than gas in the second space B, and the first space A is substantially a closed space. The air shutter device 5 has a blowing device 7 provided in the first space A in proximity to the upper part of the opening O. A discharge means 74 of the blowing device 7 takes in the cold air in the first space A from a suction port 73 and discharges it obliquely downward toward the opening O and the second space B. Pressure in the first space A becomes negative with the discharge of the cold air from the first space A, and blowoff cold air is returned into the first space A to form an air curtain with the cold air in the opening O.