A hybrid drive module, which is disposed between an engine and a transmission of a power system and includes a motor configured to provide power to the transmission, the hybrid drive module comprising: a rotor hub 43 having a rotor holder to which a rotor of the motor is fixed and a hub plate 45 extending from the rotor holder to a radial inner side; a fluid clutch connected to the rotor hub ; a first clutch pack connected to the rotor hub ; a first piston plate configured to press or release the first clutch pack ; a first accommodation space (R1) and a second accommodation space (R2) in the axial direction into which internal space of the hybrid drive module is divided by the hub plate , wherein the first accommodation space (R1) is provided in the rotor hub , configured to accommodate the fluid clutch , the first clutch pack and the first piston plate , and configured to allow a fluid for operating the fluid clutch and cooling the first clutch pack to flow and fill the first accommodation space (R1); and a second clutch pack accommodated in the second accommodation space (R2), wherein the first piston plate has a first surface directed toward the first clutch pack in an axial direction, and a second surface opposite to the first surface in the axial direction, wherein the second surface faces a first operation chamber filled with a fluid that generates pressure for moving the first piston plate toward the first clutch pack , and wherein a fluid for cooling the second clutch pack fills the second accommodation space (R2) and flows, characterized in that the first surface faces a first compensation chamber filled with a fluid with pressure lower than pressure of the fluid in the first accommodation space (R1), and the hub plate , and the fluid in the second accommodation space (R2) fills the first compensation chamber through the rotor hub . a rotor hub 43 having a rotor holder to which a rotor of the motor is fixed and a hub plate 45 extending from the rotor holder to a radial inner side; a fluid clutch connected to the rotor hub ; a first clutch pack connected to the rotor hub ; a first piston plate configured to press or release the first clutch pack ; a first accommodation space (R1) and a second accommodation space (R2) in the axial direction into which internal space of the hybrid drive module is divided by the hub plate , wherein the first accommodation space (R1) is provided in the rotor hub , configured to accommodate the fluid clutch , the first clutch pack and the first piston plate , and configured to allow a fluid for operating the fluid clutch and cooling the first clutch pack to flow and fill the first accommodation space (R1); and a second clutch pack accommodated in the second accommodation space (R2), wherein the first piston plate has a first surface directed toward the first clutch pack in an axial direction, and a second surface opposite to the first surface in the axial direction, wherein the second surface faces a first operation chamber filled with a fluid that generates pressure for moving the first piston plate toward the first clutch pack , and wherein a fluid for cooling the second clutch pack fills the second accommodation space (R2) and flows, characterized in that the first surface faces a first compensation chamber filled with a fluid with pressure lower than pressure of the fluid in the first accommodation space (R1), and the hub plate , and the fluid in the second accommodation space (R2) fills the first compensation chamber through the rotor hub . <EOS>