Support device, which is adjustable by an electric motor, for cushioning of a piece of furniture for sitting and/or lying on has a first support part, and a second support part pivotable about a pivot axis, between which a third support part is provided. Support device has an electric motor drive which has an adjusting element connected in a force-transmitting manner to the second support part by an actuating element for pivoting second support part. Actuating element has a rod-like configuration, by which the adjusting element is guided in a linearly displaceable manner in guide formed on third support part. Actuating element engages with second support part for pivoting the second support part eccentrically relative to pivot axis.
