A dual clutch comprising: a first clutch which is configured to selectively transmit rotational power of an input shaft to a first output shaft; a second clutch which is configured to selectively transmit the rotational power of the input shaft to a second output shaft; a first piston which operates the first clutch while being selectively and axially moved by axial force; a second piston which operates the second clutch while being selectively and axially moved by the axial force; and an actuator configured to transmit the axial force to the first piston or the second piston, wherein the actuator comprises: an actuator housing defining an operating piston space and formed with a housing protruding portion at a radially inner side of the operating piston space; a first operating piston transmitting the axial force to the first piston; a second operating piston transmitting the axial force to the second piston; and a partition wall disposed between the first operating piston and the second operating piston and separating the first operating piston and the second operating piston, such that an operation of the first operating piston and an operation of the second operating piston are independently controlled, characterized in that: the first operating piston is disposed in the operating piston space between an outer circumferential surface of the operating piston space and the partition wall; the second operating piston is disposed in the operating piston space between the partition wall and the housing protruding portion; and an outer circumferential surface of the second operating piston is positioned to be closer to a radially outer side of the operating piston space than is an inner circumferential surface of the first operating piston. a first clutch which is configured to selectively transmit rotational power of an input shaft to a first output shaft; a second clutch which is configured to selectively transmit the rotational power of the input shaft to a second output shaft; a first piston which operates the first clutch while being selectively and axially moved by axial force; a second piston which operates the second clutch while being selectively and axially moved by the axial force; and an actuator configured to transmit the axial force to the first piston or the second piston, wherein the actuator comprises: an actuator housing defining an operating piston space and formed with a housing protruding portion at a radially inner side of the operating piston space; a first operating piston transmitting the axial force to the first piston; a second operating piston transmitting the axial force to the second piston; and a partition wall disposed between the first operating piston and the second operating piston and separating the first operating piston and the second operating piston, such that an operation of the first operating piston and an operation of the second operating piston are independently controlled, characterized in that: the first operating piston is disposed in the operating piston space between an outer circumferential surface of the operating piston space and the partition wall; the second operating piston is disposed in the operating piston space between the partition wall and the housing protruding portion; and an outer circumferential surface of the second operating piston is positioned to be closer to a radially outer side of the operating piston space than is an inner circumferential surface of the first operating piston. an actuator housing defining an operating piston space and formed with a housing protruding portion at a radially inner side of the operating piston space; a first operating piston transmitting the axial force to the first piston; a second operating piston transmitting the axial force to the second piston; and a partition wall disposed between the first operating piston and the second operating piston and separating the first operating piston and the second operating piston, such that an operation of the first operating piston and an operation of the second operating piston are independently controlled, characterized in that: the first operating piston is disposed in the operating piston space between an outer circumferential surface of the operating piston space and the partition wall; the second operating piston is disposed in the operating piston space between the partition wall and the housing protruding portion; and an outer circumferential surface of the second operating piston is positioned to be closer to a radially outer side of the operating piston space than is an inner circumferential surface of the first operating piston. the first operating piston is disposed in the operating piston space between an outer circumferential surface of the operating piston space and the partition wall; the second operating piston is disposed in the operating piston space between the partition wall and the housing protruding portion; and an outer circumferential surface of the second operating piston is positioned to be closer to a radially outer side of the operating piston space than is an inner circumferential surface of the first operating piston.