An actuating device for an active control suspension system which is provided at both ends of a sub-frame of a vehicle body and connected to one end of an assist link having the other end mounted at a knuckle and which changes a position of a mounting point of the assist link at the vehicle body, may include a member bracket fixedly mounted at each end of the sub-frame, provided with openings formed at both sides and an upper surface thereof, and formed of a pair of slide grooves having arc shape at the both ends thereof to slidably receive a pair of slide plates therein; an actuator connected to both slide plates through a pin-bolt unit; and a cam-bolt unit assembling a bush of the assist link with both slide plates and setting an initial position of the mounting point of the assist link at the vehicle body.