A refrigerator, comprising: a body; an ice making compartment provided at an inside the body; a cool air supplying apparatus having a compressor, a condenser, an expansion apparatus (54, 55), an evaporator (34, 44), and a refrigerant pipe, at least a portion of which is disposed at an inside the ice making compartment so that cooling energy is supplied to the ice making compartment; and an ice maker having an ice making tray configured to make contact with the refrigerant pipe of the ice making compartment to directly receive the cooling energy from the refrigerant pipe of the ice making compartment, and a drain duct disposed at a lower side of the ice making tray; wherein the ice making tray comprises: a bottom; a sidewall extended from the bottom toward an upper side thereof to form an ice making space; and a plurality of partition walls configured to divide the ice making space into a plurality of unit ice making spaces (349a, 349b) characterized in that the ice making tray further comprises; a plurality of communicating parts formed at the plurality of partition walls to communicate adjacent unit ice making spaces to each other among the plurality of unit ice making spaces; an opening formed at the sidewall so that, in a case when water supplied to the ice making space has an amount exceeding a predetermined amount, the excess amount of water is discharged to an outside the ice making tray; a derailment prevention wall extended toward an upper side from the sidewall to prevent the ice separated from the ice making space from be derailed, and the opening is consecutively formed at the sidewall and the derailment prevention wall. a body; an ice making compartment provided at an inside the body; a cool air supplying apparatus having a compressor, a condenser, an expansion apparatus (54, 55), an evaporator (34, 44), and a refrigerant pipe, at least a portion of which is disposed at an inside the ice making compartment so that cooling energy is supplied to the ice making compartment; and an ice maker having an ice making tray configured to make contact with the refrigerant pipe of the ice making compartment to directly receive the cooling energy from the refrigerant pipe of the ice making compartment, and a drain duct disposed at a lower side of the ice making tray; wherein the ice making tray comprises: a bottom; a sidewall extended from the bottom toward an upper side thereof to form an ice making space; and a plurality of partition walls configured to divide the ice making space into a plurality of unit ice making spaces (349a, 349b) characterized in that the ice making tray further comprises; a bottom; a sidewall extended from the bottom toward an upper side thereof to form an ice making space; and a plurality of partition walls configured to divide the ice making space into a plurality of unit ice making spaces (349a, 349b) characterized in that the ice making tray further comprises; a plurality of communicating parts formed at the plurality of partition walls to communicate adjacent unit ice making spaces to each other among the plurality of unit ice making spaces; an opening formed at the sidewall so that, in a case when water supplied to the ice making space has an amount exceeding a predetermined amount, the excess amount of water is discharged to an outside the ice making tray; a derailment prevention wall extended toward an upper side from the sidewall to prevent the ice separated from the ice making space from be derailed, and the opening is consecutively formed at the sidewall and the derailment prevention wall.