Steering column for a motor vehicle, which is adjustable in at least the longitudinal direction thereof or in the vertical direction thereof, comprising - a casing tube, which rotatably supports a steering spindle, - a holding part, which can be connected to the body of the motor vehicle and has two lateral cheeks (19, 20), between which the casing tube is arranged, - an electromechanical fixing device, in the release position of which the casing tube can be adjusted relative to the holding part at least in the longitudinal direction or in the vertical direction of the steering column and in the fixing position of which the set position of the casing tube is fixed relative to the holding part, wherein the fixing device comprises • a clamping bolt, which passes through the lateral cheeks (19, 20) of the holding part and can be rotated about its axis by means of an electric motor arranged in a housing (26, 27) as the fixing device is opened and closed, and • a stroke-generating mechanism and a support bearing, wherein the lateral cheeks (19, 20) of the holding part and the casing tube are arranged between the stroke-generating mechanism and the support bearing, characterized in that the stroke-generating mechanism has two stroke-generating disks (24, 241, 242, 25, 251, 252), wherein a first stroke-generating disk (24, 241, 242) is connected for conjoint rotation to the clamping bolt and a second stroke-generating disk (25, 251, 252) is guided on the clamping bolt in such a way as to be axially movable in the housing (26, 27), and wherein the housing (26, 27) is mounted in a floating manner on the second stroke-generating disk (25, 251, 252), wherein no additional fastening points are provided for attaching the fixing device to the steering column. - a casing tube, which rotatably supports a steering spindle, - a holding part, which can be connected to the body of the motor vehicle and has two lateral cheeks (19, 20), between which the casing tube is arranged, - an electromechanical fixing device, in the release position of which the casing tube can be adjusted relative to the holding part at least in the longitudinal direction or in the vertical direction of the steering column and in the fixing position of which the set position of the casing tube is fixed relative to the holding part, wherein the fixing device comprises • a clamping bolt, which passes through the lateral cheeks (19, 20) of the holding part and can be rotated about its axis by means of an electric motor arranged in a housing (26, 27) as the fixing device is opened and closed, and • a stroke-generating mechanism and a support bearing, wherein the lateral cheeks (19, 20) of the holding part and the casing tube are arranged between the stroke-generating mechanism and the support bearing, characterized in that • a clamping bolt, which passes through the lateral cheeks (19, 20) of the holding part and can be rotated about its axis by means of an electric motor arranged in a housing (26, 27) as the fixing device is opened and closed, and • a stroke-generating mechanism and a support bearing, wherein the lateral cheeks (19, 20) of the holding part and the casing tube are arranged between the stroke-generating mechanism and the support bearing, characterized in that