The invention relates to a hydraulic system for actuating a continuously variable belt-driven conical-pulley transmission having two conical pulleys encircled by an endless torque-transmitting means, each of which comprises two conical disks, one of which is axially movable depending on the pressure in an associated pressing chamber, and having a torque sensor which includes a torque sensing chamber that is connected to a hydraulic energy source and is linked with the pressing chambers.The invention is distinguished by the fact that the pressing chambers are connected via a first hydraulic resistance element to the torque sensing chamber, and via a second hydraulic resistance element to an additional pressure chamber, in which a lower pressure prevails than in the pressing chambers and/or the torque sensing chamber.