Abstract: An ice thermal storage refrigerator unit includes a brine path consisting essentially of a refrigerator, an ice thermal storage tank, a water heat exchanger, a brine pump, and control valves, which are connected by piping, and a cold water path consisting essentially of the water heat exchanger, a cooling load, and a cold water pump, which are connected by piping, so that brine is cooled in the refrigerator, and water in the ice thermal storage tank is frozen by the brine, thereby storing heat, and when heat is to be discharged, the brine is cooled by heat of fusion of the ice in the ice thermal storage tank, and the brine is introduced into the water heat exchanger to cool cold water, thereby taking out a cooling capacity.