Abstract: A chuck drive system, especially for a rotating clamping device of a machine tool, includes a rotating chuck cylinder, a stationary frame positioned adjacent the chuck cylinder, and a piston which subdivides the cylinder into two pressure chambers and is formed with a piston rod having one end rotatably supported in the stationary frame. Fluid under pressure is supplied to the pressure chambers, whereby check valves are positioned in the passageways to the pressure chambers to maintain the fluid pressure in the pressure chambers. In order to monitor the fluid pressure in the pressure chambers, a pressure monitoring unit is provided which includes pressure sensors that are respectively assigned to the pressure chambers for determining the fluid pressure in the pressure chambers separately and independently from one another.