an apparatus body;

a water tank which is provided in the apparatus body and which accommodates water flowing in from a water supply source;

a cold water generation pipe which is provided in the apparatus body so as to be connected to the water tank, and which allows the water accommodated in the water tank to flow thereto, to then be discharged; and

a cooling unit which is mounted on an outer surface of the apparatus body, and which cools the apparatus body so that the water accommodated in the water tank and the water flowing in the cold water generation pipe is cooled,

wherein the apparatus body has a tank insertion space having one open side so that at least a portion of the water tank is inserted thereinto,

wherein the water tank includes a tank main body which is inserted into the tank insertion space and having one open side, and a tank cover which is coupled to the apparatus body so as to cover the one open side of the tank main body, and having an inlet which allows water from the water supply source to flow into the tank main body and a connector connected to the cold water generation pipe,

wherein the apparatus body and the water tank include a material having thermal conductivity of 10 W/(m·K) or higher at room temperature, and

wherein water flowing in from the water supply source is accommodated in the water tank and cooled by water flowing in the cold water generation pipe, and the water cooled in the water tank is discharged to outside after being cooled by the cooling unit while flowing in the cold water generation pipe.