An actuating device has a linearly-movable fluidly operated piston drive (1). A pivot shaft (3) is movably, rotatably mounted in a housing (2). A lever arm (4) is connected with the pivot shaft (3) in a torsionally rigid manner. An adjustment mechanism (5) connects the piston drive (1) with the pivot shaft (3). A damping device (6) dampens movement of the lever arm (4). The damping device (6) is associated with the housing (2) and with the pivot shaft (3).