A refrigerator comprising a cool air supply structure of a storage receptacle, comprising: one or more box casings detachably installed in a refrigerating chamber of the refrigerator, each box casing having a mounting space and a channel through which cool air flows, the cool air being supplied from a cool air supply source through a cool air supply port formed in a side surface of the refrigerating chamber; and one or more storage receptacles, each storage receptacle being withdrawably installed in the mounting space, wherein food accommodated in an accommodation space provided in the storage receptacle is indirectly cooled by the cool air that flows through the channel, characterized in that the channel comprises a first channel (150P1) provided in a side surface of the box casing adjacent to the side surface of the refrigerating chamber to communicate with the cool air supply port, and a second channel (150P2) provided in an upper portion of the box casing to communicate with the first channel (150P1), wherein the box casing comprises an upper cover provided with the second channel (150P2) and defining an upper external appearance of the box casing, and a lower casing fixed to the upper cover and defining both sides, rear and bottom external appearances of the box casing, the lower casing being provided with the first channel (150P1), wherein the first channel (150P1) is defined in the mounting space by an inner side surface of the box casing and an inner surface of a duct member fixed to the inner side surface of the box casing, and the second channel (150P2) is defined by a bottom surface of an upper plate, an upper surface of a lower plate and an inner upper end of both side surfaces and a rear surface of the lower casing, the upper and lower plates (152, 153) constituting the upper cover and being respectively fixed to the lower casing to be vertically spaced apart by a predetermined interval from each other. one or more box casings detachably installed in a refrigerating chamber of the refrigerator, each box casing having a mounting space and a channel through which cool air flows, the cool air being supplied from a cool air supply source through a cool air supply port formed in a side surface of the refrigerating chamber; and one or more storage receptacles, each storage receptacle being withdrawably installed in the mounting space, wherein food accommodated in an accommodation space provided in the storage receptacle is indirectly cooled by the cool air that flows through the channel, characterized in that the channel comprises a first channel (150P1) provided in a side surface of the box casing adjacent to the side surface of the refrigerating chamber to communicate with the cool air supply port, and a second channel (150P2) provided in an upper portion of the box casing to communicate with the first channel (150P1), wherein the box casing comprises an upper cover provided with the second channel (150P2) and defining an upper external appearance of the box casing, and a lower casing fixed to the upper cover and defining both sides, rear and bottom external appearances of the box casing, the lower casing being provided with the first channel (150P1), wherein the first channel (150P1) is defined in the mounting space by an inner side surface of the box casing and an inner surface of a duct member fixed to the inner side surface of the box casing, and the second channel (150P2) is defined by a bottom surface of an upper plate, an upper surface of a lower plate and an inner upper end of both side surfaces and a rear surface of the lower casing, the upper and lower plates (152, 153) constituting the upper cover and being respectively fixed to the lower casing to be vertically spaced apart by a predetermined interval from each other.