A refrigerator comprising a cool air supply structure of a storage receptacle, which includes a main body having a storage space provided therein and a door for selectively opening or closing the storage space, the cool air supply structure, comprising: at least one receptacle casing detachably installed into the storage space and having a mounting space provided therein so that a storage receptacle is moved into or out of the mounting space; and a channel provided in the at least one receptacle casing so that cool air flows in the channel, wherein food received in the storage receptacle is indirectly cooled by the cool air flowing in the channel, the receptacle casing includes a lower casing formed in the shape of a hexahedron with a front face and an upper portion opened, an upper casing formed in the shape of a hexahedron with a lower portion opened and fixed to a top end of the lower casing, and an inner plate fixed to an interior of the lower casing corresponding to a lower portion of the upper casing; and the channel is defined by an upper surface and both side surfaces of the upper casing and an upper surface of the inner plate, and wherein insertion slots are respectively provided in top ends of both inner sides of the lower casing to extend in a fore and aft direction; and both side ends of the inner plate are inserted into the insertion slots, whereby the lower casing and the inner plate are fixed to each other, wherein among a freezing chamber and a refrigerating chamber that the storage space includes, the receptacle casings are detachably installed into the refrigerating chamber, and characterised in that the cool air in the refrigerating chamber is transferred to the channel through a cool air duct formed to vertically extend and installed to a center of a rear surface of the refrigerating chamber, the cool air duct having cool air supply holes formed therein, wherein the cool air flowing in the channel is introduced through a cool air inlet provided in a rear surface of the receptacle casing to communicate with any one of cool air supply holes of the cool air duct; and the cool air flowing in the channel to indirectly cool the food received in the receiving space is discharged to the refrigerating chamber through a cool air outlet provided in the rear surface of the receptacle casing, wherein the cool air is provided to the channel of the inner plate when the cool air supply holes and cool air return holes are in contact with the inner plate wherein the inner plate is mounted along the insertion slots; and wherein each of the insertion slots is formed between a pair of insertion ribs (53B, 53C) that are provided to extend from the top ends of both of the inner sides of the lower casing in its longitudinal direction and to protrude in opposite directions. at least one receptacle casing detachably installed into the storage space and having a mounting space provided therein so that a storage receptacle is moved into or out of the mounting space; and a channel provided in the at least one receptacle casing so that cool air flows in the channel, wherein food received in the storage receptacle is indirectly cooled by the cool air flowing in the channel, the receptacle casing includes a lower casing formed in the shape of a hexahedron with a front face and an upper portion opened, an upper casing formed in the shape of a hexahedron with a lower portion opened and fixed to a top end of the lower casing, and an inner plate fixed to an interior of the lower casing corresponding to a lower portion of the upper casing; and the channel is defined by an upper surface and both side surfaces of the upper casing and an upper surface of the inner plate, and wherein insertion slots are respectively provided in top ends of both inner sides of the lower casing to extend in a fore and aft direction; and both side ends of the inner plate are inserted into the insertion slots, whereby the lower casing and the inner plate are fixed to each other, wherein among a freezing chamber and a refrigerating chamber that the storage space includes, the receptacle casings are detachably installed into the refrigerating chamber, and characterised in that the cool air in the refrigerating chamber is transferred to the channel through a cool air duct formed to vertically extend and installed to a center of a rear surface of the refrigerating chamber, the cool air duct having cool air supply holes formed therein, wherein the cool air flowing in the channel is introduced through a cool air inlet provided in a rear surface of the receptacle casing to communicate with any one of cool air supply holes of the cool air duct; and the cool air flowing in the channel to indirectly cool the food received in the receiving space is discharged to the refrigerating chamber through a cool air outlet provided in the rear surface of the receptacle casing, wherein the cool air is provided to the channel of the inner plate when the cool air supply holes and cool air return holes are in contact with the inner plate wherein the inner plate is mounted along the insertion slots; and wherein each of the insertion slots is formed between a pair of insertion ribs (53B, 53C) that are provided to extend from the top ends of both of the inner sides of the lower casing in its longitudinal direction and to protrude in opposite directions.