PURPOSE: To miniaturize and lighten a portable cooling device and to enable cold soft drinks or beer or the like to be taken as desired even at an outdoor circumstance by a method wherein a refrigerant gasified by pressure reduction such as liquid nitrogen is enclosed adjacent to a cooling chamber and further a part of a passage for discharging the refrigerant is provided with a previously formed refrigerant chamber.

CONSTITUTION: A cooling chamber 3 for storing a cooled item and a refrigerant chamber 4 are stored in a portable container 1. At the refrigerant chamber 4, refrigerant 5 such as liquid nitrogen, liquid freons or the like is enclosed in a sealed container made of synthetic resin, a discharging passage 6 extending from a predetermined position at an upper side to a bottom part of the chamber and an outlet of the discharging passage 6 are sealed and then a projection 7 projection outwardly is integrally formed with the outlet. The cooling chamber 3 is axially and slidably supported within the container 1 and fitted therein. An object to be cooled is stored in the cooling chamber. A predetermined spacing is kept between the bottom part of the cooling chamber 3 and the refrigerant chamber 4. As the cooling chamber 3 is displaced downwardly, the projection 7 is broken at its root part to cause an outlet of the discharging passage 6 to be opened or communicated with the surrounding area, the refrigerant discharged in its atomized state passes through a gasification passage 8 while removing a gasification heat from the surrounding area through its gasification and then the refrigerant is discharged through a drain hole 9 into the surrounding atmosphere.