COOLING BOX

Energy saving performance is to be enhanced while a temperature in a thermally insulated casing of a cooling box being maintained at a fixed value. [MEANS FOR SOLVING THE PROBLEM] A cooling box configured to perform temperature control by supplying cold air into an interior thereof when an internal temperature thereof is higher than a set temperature so that the internal temperature of the cooling box to store an item to be refrigerated becomes equal to the predetermined set temperature, and supplying warm air into the interior thereof when the internal temperature thereof is lower than the set temperature so that the internal temperature of the cooling box reaches the set temperature, the cooling box comprising: a control device including an ambient temperature sensor configured to detect an ambient temperature of the cooling box, the control device configured to adjust a supply amount of warm air into the cooling box after stopping supply of cold air into the cooling box based on the temperature detected by the ambient temperature sensor.