PURPOSE: To prevent frosting of an indoor blower even if defrosting are about twice a day, to maintain a predetermined cold insulation capacity by preventing a decrease in a discharging air flow rate and to prevent a decrease in quality of an easily meltable commodity such as ice cream.

CONSTITUTION: An interior of a display case body 1 formed with an opening 9 for inputting and outputting a commodity at an upper surface of a refrigerating cold storage display case is partitioned into a commodity storage chamber 10 and a chilled gas circulating passage 4 and arranged with a cooler 3 in the passage 4, and a plurality of indoor blowers 2a, 2b attached to a cooler 3 are arranged. The blowers 2a, 2b are sequentially operated between a defrosting operation and next defrosting operation, and a time in which frosting for reducing an air flow rate does not occur at the blowers 2a, 2b is set as a one time operating time.