A clamping device for clamping a workpiece or a tool or a tool holder to a machine component of a machine tool, including an axially movable tension rod, a clamping assembly which can be moved by the tension rod between a clamped position and a released position, a spring assembly dedicated to the tension rod for generating the clamping and draw-in force of the clamping assembly, and a releasing unit by which the clamping assembly can be moved by the tension rod against the force of the spring assembly into the released position. The spring assembly has a minimum of one spring unit with a plurality of flexible spring members disposed between a first and a second spring holder, with the first and second spring holders being secured against torsion relative to the tension rod.