A refrigerator comprising: a cabinet suitable to be installed to pass through or inserted into a door or a wall and forming a storage compartment for storing goods; a housing coupled to or formed integrally with a lower part of the cabinet; an outdoor side door configured to open or close a front side of the storage compartment and exposed to an outside of a space, the door or the wall being a boundary of the space; an indoor side door configured to open or close a rear side of the storage compartment and exposed to an inside of the space; a cold air supply device, at least a part of which is disposed in the housing, configured to make air in the storage compartment cold; the refrigerator being characterised by the housing having a front surface suitable for contact with a rear surface of the door or wall when the refrigerator is installed to pass through or inserted into the door or wall; a printed circuit board, PCB, on which electrical components for controlling the driving of at least the cold air supply device are mounted; and a controller provided in the PCB to control the driving of the cold air supply device, wherein the housing is provided with: a suction port configured to have outside air suctioned through it; and a discharge port (156, 157, 158, 159) configured to discharge the air introduced through the suction port, wherein the housing is configured to provide an air flow passage within the housing between the suction port and the discharge port, and wherein the PCB (41, 42) is disposed within the air flow passage. a cabinet suitable to be installed to pass through or inserted into a door or a wall and forming a storage compartment for storing goods; a housing coupled to or formed integrally with a lower part of the cabinet; an outdoor side door configured to open or close a front side of the storage compartment and exposed to an outside of a space, the door or the wall being a boundary of the space; an indoor side door configured to open or close a rear side of the storage compartment and exposed to an inside of the space; a cold air supply device, at least a part of which is disposed in the housing, configured to make air in the storage compartment cold; the refrigerator being characterised by the housing having a front surface suitable for contact with a rear surface of the door or wall when the refrigerator is installed to pass through or inserted into the door or wall; a printed circuit board, PCB, on which electrical components for controlling the driving of at least the cold air supply device are mounted; and a controller provided in the PCB to control the driving of the cold air supply device, wherein the housing is provided with: a suction port configured to have outside air suctioned through it; and a discharge port (156, 157, 158, 159) configured to discharge the air introduced through the suction port, wherein the housing is configured to provide an air flow passage within the housing between the suction port and the discharge port, and wherein the PCB (41, 42) is disposed within the air flow passage. a suction port configured to have outside air suctioned through it; and a discharge port (156, 157, 158, 159) configured to discharge the air introduced through the suction port, wherein the housing is configured to provide an air flow passage within the housing between the suction port and the discharge port, and wherein the PCB (41, 42) is disposed within the air flow passage.