To approx. uniformly and entirely perform the cooling or the heating of a thermally conductive body by providing an electrothermal exchange element group on the surface of the thermally conductive body, which is confronted with the opening of a heat insulating container.

A cold-keeping pit 2 has a box-shaped heat insulating container 5 of which the top is open, and two slide top plates 6a, 6b which open to the right and the left to open/ close the top opening, are supported by a frame-shaped supporting member 7. A container-form first thermally conductive body 8 is arranged so as to be tightly joined to the internal wall of the heat insulating container 5. On the surface of the first thermally conductive body 8, which is confronted with the opening of the heat insulating container 5, i.e., on the rear side of the approx. center of the bottom part of the first thermally conductive body 8, a plurality of block-shaped second thermally conductive bodies 9, are provided, and to the lower surface of each second thermally conductive body 9, a heat absorbing side water jacket 11 is tightly joined with an electrothermal exchange element group 10. Therefore, when an article 39 to be cooled is placed in the heat insulating container 5, the article 39 to be cooled inevitably comes into contact with the bottom part of the first thermally conductive body 8 directly, and can be cooled by the electrothermal exchange elements 10 through the bottom part, and for this reason, the cooling effect is extremely high.