The present invention relates to a hybrid drive module, which may ensure pressing pressure for a lock-up clutch while reducing, through a simple structure, operating pressure of a piston for pressing a lock-up clutch disposed in a space to which fluid pressure of a torque converter is applied, the hybrid drive module having a small number of components and being capable of being easily assembled. The present invention is accomplished by providing a compensation chamber of the piston and filling the compensation chamber with a low-pressure fluid. In addition, the low-pressure fluid may be used as a fluid for lubricating and cooling an engine clutch.