A refrigerator comprising: a body; a storage chamber (20, 30, 620, 630) defined in the body while having an opened front side; a door (21, 22, 31; 621, 631) to open or close the opened front side of the storage chamber; a water tank to store clean water; a carbonated water production module (100, 570) mounted to a back surface of the door, the carbonated water production module comprising a carbon dioxide gas cylinder stored with high-pressure carbon dioxide gas, and a carbonated water tank to produce carbonated water through mixing of the clean water with the carbon dioxide gas, and to store carbonated water; characterized by a dispensation space formed at a front surface of the door; a carbonated water discharge line to connect the carbonated water tank and the dispensation space, so as to discharge the carbonated water in the dispensation space; a carbonated water regulator provided at the carbonated water discharge line and configured to control carbonated water from the carbonated water tank to be discharged at a predetermined pressure, the carbonated water regulator including a regulator body, a static pressure hole to allow carbonated water to flow through the regulator body, and an opening/closing member to open or close at least a portion of the static pressure hole wherein a first space is defined in the body by an inner surface of the body and a bellows having elasticity, the first space accommodating a first regulator elastic member, a second space partitioned from the first space by the bellows while communicating with a carbonated water outlet to discharge the carbonated water, and a third space partitioned from the second space by the static pressure hole while communicating with a carbonated water inlet to receive the carbonated water, the third space accommodating a second regulator elastic member and the opening/closing member. a body; a storage chamber (20, 30, 620, 630) defined in the body while having an opened front side; a door (21, 22, 31; 621, 631) to open or close the opened front side of the storage chamber; a water tank to store clean water; a carbonated water production module (100, 570) mounted to a back surface of the door, the carbonated water production module comprising a carbon dioxide gas cylinder stored with high-pressure carbon dioxide gas, and a carbonated water tank to produce carbonated water through mixing of the clean water with the carbon dioxide gas, and to store carbonated water; characterized by a dispensation space formed at a front surface of the door; a carbonated water discharge line to connect the carbonated water tank and the dispensation space, so as to discharge the carbonated water in the dispensation space; a carbonated water regulator provided at the carbonated water discharge line and configured to control carbonated water from the carbonated water tank to be discharged at a predetermined pressure, the carbonated water regulator including a regulator body, a static pressure hole to allow carbonated water to flow through the regulator body, and an opening/closing member to open or close at least a portion of the static pressure hole wherein a first space is defined in the body by an inner surface of the body and a bellows having elasticity, the first space accommodating a first regulator elastic member, a second space partitioned from the first space by the bellows while communicating with a carbonated water outlet to discharge the carbonated water, and a third space partitioned from the second space by the static pressure hole while communicating with a carbonated water inlet to receive the carbonated water, the third space accommodating a second regulator elastic member and the opening/closing member.