A control apparatus for an electromechanical-brake-booster of a vehicle, having: an electronic-device to control an electric-motor of the electromechanical-brake-booster so that an output piston, connected indirectly to the electric-motor, of the electromechanical-brake-booster is displaceable out of its initial-position by the controlled electric-motor, such that only after a displacement of the output-piston out of its initial-position by at least a predefined limit displacement travel does a frictional engagement exist between the output-piston and an input-piston that is indirectly connected to the brake-pedal and is displaced by the actuation of the brake-pedal, and such that a speed of the output-piston displaced out of its initial-position by less than the limit displacement travel is at first increased from a reference-speed to a maximum-speed and is then reduced from the maximum-speed to the reference-speed. The invention furthermore relates to a method for operating an electromechanical-brake-booster of a vehicle.