A refrigerator comprising: a cabinet defining a storage space; a door opening and closing the storage space; and a transparent panel assembly being controlled by a control unit, the transparent panel assembly is disposed on at least one area of the door, on which a see-through part through which an interior of the refrigerator is seen is disposed, wherein the refrigerator further comprises: a first light (57, 121) disposed closer to the interior of the refrigerator than the transparent panel assembly to brighten an area of the interior of the refrigerator that is viewed by the see-through part, wherein the transparent panel assembly comprises: a plurality of transparent panels spaced apart from each other to define an accommodation space; a transparent display disposed in the accommodation space to output a screen; and a second light brightening the display within the accommodation space, wherein the display, the first light (57, 121), and the second light are selectively turned off according to manipulation of a user on an input manipulation unit so as the see-through part of the transparent panel assembly to be converted into an opaque state in which the interior of the refrigerator is not seen and the screen is not outputted on the see-through part and a transparent state in which the interior of the refrigerator is seen, wherein in the transparent state, the screen is outputted on the see-through part while the interior of the refrigerator is seen, wherein the display, the first light (57, 121), and the second light are turned off to maintain the opaque state of the see-through part, and when an input on the input manipulation unit is detected in the opaque state of the see-through part, the opaque state of the see-through part is converted depending on this input into one of: a first state being a transparent one in which the first light (57, 121) is turned on, and the second light is turned off so that the interior of the refrigerator is seen; a second state being a transparent one in which all the first light (57, 121), the second light, and the display are turned on so that the screen is outputted on the see-through part while the interior of the refrigerator is seen; and a third state being an opaque one in which the first light (57, 121) is turned off, and the second light and the display are turned on so that only the screen is outputted on the see-through part while the interior of the refrigerator is not seen. a first light (57, 121) disposed closer to the interior of the refrigerator than the transparent panel assembly to brighten an area of the interior of the refrigerator that is viewed by the see-through part, wherein the transparent panel assembly comprises: a plurality of transparent panels spaced apart from each other to define an accommodation space; a transparent display disposed in the accommodation space to output a screen; and a second light brightening the display within the accommodation space, wherein the display, the first light (57, 121), and the second light are selectively turned off according to manipulation of a user on an input manipulation unit so as the see-through part of the transparent panel assembly to be converted into an opaque state in which the interior of the refrigerator is not seen and the screen is not outputted on the see-through part and a transparent state in which the interior of the refrigerator is seen, wherein in the transparent state, the screen is outputted on the see-through part while the interior of the refrigerator is seen, wherein the display, the first light (57, 121), and the second light are turned off to maintain the opaque state of the see-through part, and when an input on the input manipulation unit is detected in the opaque state of the see-through part, the opaque state of the see-through part is converted depending on this input into one of: a first state being a transparent one in which the first light (57, 121) is turned on, and the second light is turned off so that the interior of the refrigerator is seen; a second state being a transparent one in which all the first light (57, 121), the second light, and the display are turned on so that the screen is outputted on the see-through part while the interior of the refrigerator is seen; and a third state being an opaque one in which the first light (57, 121) is turned off, and the second light and the display are turned on so that only the screen is outputted on the see-through part while the interior of the refrigerator is not seen. a first state being a transparent one in which the first light (57, 121) is turned on, and the second light is turned off so that the interior of the refrigerator is seen; a second state being a transparent one in which all the first light (57, 121), the second light, and the display are turned on so that the screen is outputted on the see-through part while the interior of the refrigerator is seen; and a third state being an opaque one in which the first light (57, 121) is turned off, and the second light and the display are turned on so that only the screen is outputted on the see-through part while the interior of the refrigerator is not seen.