An ice-making device for a refrigerator having a refrigerator door, comprising: a water tank configured to be detachably mounted to a rear surface of the refrigerator door; a first ice-making housing configured to be detachably mounted to the rear surface of the refrigerator door below the water tank and provided with a predetermined installation space therein; an ice tray pivotally mounted into the installation space of the first ice-making housing and provided with an ice-making groove in which water supplied from the water tank is frozen into ice; a second ice-making housing configured to be detachably mounted to the rear surface of the refrigerator door below the first ice-making housing and provided with a predetermined installation space therein; an ice bank for storing ice made in the ice tray; and a guide box for moving forward or rearward of the installation space of the second ice-making housing in a state where the ice bank is seated thereon such that the ice bank can be received in or withdrawn from the installation space of the second ice-making housing through a home bar provided in the refrigerator door, wherein the ice bank and the guide box can be received in or withdrawn from the installation space of the second ice-making housing, characterized in that the ice-making device further comprises a tray cover mounted in the installation space of the first ice-making housing to be vertically pivoted in cooperation with a pivot motion of the ice tray and to selectively open or close the ice-making groove, wherein the tray cover is provided with a supply port formed at a position deviated from a region where the water is supplied from the water tank to the ice tray through the supply port of the first ice-making housing, and a water guide surface downwardly inclined toward the supply port of the tray cover to guide the water into the supply port of the tray cover. a water tank configured to be detachably mounted to a rear surface of the refrigerator door; a first ice-making housing configured to be detachably mounted to the rear surface of the refrigerator door below the water tank and provided with a predetermined installation space therein; an ice tray pivotally mounted into the installation space of the first ice-making housing and provided with an ice-making groove in which water supplied from the water tank is frozen into ice; a second ice-making housing configured to be detachably mounted to the rear surface of the refrigerator door below the first ice-making housing and provided with a predetermined installation space therein; an ice bank for storing ice made in the ice tray; and a guide box for moving forward or rearward of the installation space of the second ice-making housing in a state where the ice bank is seated thereon such that the ice bank can be received in or withdrawn from the installation space of the second ice-making housing through a home bar provided in the refrigerator door, wherein the ice bank and the guide box can be received in or withdrawn from the installation space of the second ice-making housing, characterized in that the ice-making device further comprises a tray cover mounted in the installation space of the first ice-making housing to be vertically pivoted in cooperation with a pivot motion of the ice tray and to selectively open or close the ice-making groove, wherein the tray cover is provided with a supply port formed at a position deviated from a region where the water is supplied from the water tank to the ice tray through the supply port of the first ice-making housing, and a water guide surface downwardly inclined toward the supply port of the tray cover to guide the water into the supply port of the tray cover.