A refrigerator, comprising: an insulating case; a storage compartment (3, 4, 5, 6, 7) being at least divided into a refrigerator compartment and a freezer compartment (4, 5, 6); a space portion; a refrigerator supply air passage for enabling the air to flow to the refrigerator compartment; an air passage control device connecting the refrigerator supply air passage and the space portion, the air passage control device being provided in the refrigerator supply air passage; a freezer supply air passage adapted for enabling air to flow into the freezer compartment (4, 5, 6); a return air passage, adapted for enabling the air from the storage compartment (3, 4, 5, 6, 7) to flow through; a cooling compartment, that is inside the insulating case disposed at a rear side of the space portion, the cooling compartment and the space portion being separated from each other by a cooling compartment separating wall made of synthetic resin, the cooling compartment having an air supply opening portion that connects the space portion to the cooling compartment and a return air opening portion for enabling the air from the return air passage to flow in; an evaporator, disposed inside the cooling compartment adapted for cooling the air that flows in from the return air opening portion; a defrosting heater, arranged below the evaporator; and an air supply device, disposed on the air supply opening portion, characterized in that, the space portion is separated from the supply air passage and formed in the rear side of the freezer supply air passage, the freezer supply air passage and the space portion being separated from each other by a separator made of synthetic resin, the separator being arranged between the freezer compartment (4, 5, 6) and the cooling compartment and at the same time between the freezer supply air passage and the space portion, the freezer supply air passage is separated from the freezer compartment (4, 5, 6) by an air passage separating wall with air permitted to flow from the freezer supply air passage to the freezer compartment (4, 5, 6) via at least one blowing vent (22, 23, 24) and wherein further a freely controllable first opening portion is disposed in the separator and adjustable so as to control air flow between the space portion and the freezer supply air passage with the first opening portion being adapted to be controlled by a motorized shielding plate or another control apparatus; and a freely controllable second opening portion that is disposed in a separating region between the space portion and the return air passage or between the space portion and the cooling compartment, the second opening portion being adapted to be controlled by a motorized shielding plate or another control apparatus. an insulating case; a storage compartment (3, 4, 5, 6, 7) being at least divided into a refrigerator compartment and a freezer compartment (4, 5, 6); a space portion; a refrigerator supply air passage for enabling the air to flow to the refrigerator compartment; an air passage control device connecting the refrigerator supply air passage and the space portion, the air passage control device being provided in the refrigerator supply air passage; a freezer supply air passage adapted for enabling air to flow into the freezer compartment (4, 5, 6); a return air passage, adapted for enabling the air from the storage compartment (3, 4, 5, 6, 7) to flow through; a cooling compartment, that is inside the insulating case disposed at a rear side of the space portion, the cooling compartment and the space portion being separated from each other by a cooling compartment separating wall made of synthetic resin, the cooling compartment having an air supply opening portion that connects the space portion to the cooling compartment and a return air opening portion for enabling the air from the return air passage to flow in; an evaporator, disposed inside the cooling compartment adapted for cooling the air that flows in from the return air opening portion; a defrosting heater, arranged below the evaporator; and an air supply device, disposed on the air supply opening portion, characterized in that, the space portion is separated from the supply air passage and formed in the rear side of the freezer supply air passage, the freezer supply air passage and the space portion being separated from each other by a separator made of synthetic resin, the separator being arranged between the freezer compartment (4, 5, 6) and the cooling compartment and at the same time between the freezer supply air passage and the space portion, the freezer supply air passage is separated from the freezer compartment (4, 5, 6) by an air passage separating wall with air permitted to flow from the freezer supply air passage to the freezer compartment (4, 5, 6) via at least one blowing vent (22, 23, 24) and wherein further a freely controllable first opening portion is disposed in the separator and adjustable so as to control air flow between the space portion and the freezer supply air passage with the first opening portion being adapted to be controlled by a motorized shielding plate or another control apparatus; and a freely controllable second opening portion that is disposed in a separating region between the space portion and the return air passage or between the space portion and the cooling compartment, the second opening portion being adapted to be controlled by a motorized shielding plate or another control apparatus.