To properly cool each showcase and effectively use the inner part of a main body.

A part of cold air supplied for cooling a showcase 1 is recovered to a cooling source. The cold air supplied for cooling of the quantity substantially equal to that of the cold air cooled lower than the set temperature of the showcase in the cooling source is mixed with the rest of the cold air which is not recovered to the cooling source in the showcase 1. The mixed cold air is circulated so as to pass a goods display part 3. Then, when the temperature of the case 1 rises higher than the set temperature, the quantity of cold air to be supplied to the case 1 and the quantity of cold air for recovery to be recovered to the cooling source are adjusted to be increased. When the temperature of the case 1 is lower than the set temperature, the quantity of cold air to be supplied and the quantity of ventilation of cold air to be recovered are adjusted to become 0 or to be decreased. A part of the cold air used for cooling the case is recovered to an air guide passage 21 in the case 1 and circulated in the case so as to pass the front part of the goods display part 3 of the case 1.