In the case of an actuator having a rotation angle sensor with a magnet, no satisfying solution has yet been found for the attachment of the magnet. The invention relates to an actuator having a rotation angle sensor, the magnet of the rotation angle sensor being provided with a plastic cover. The plastic cover and magnet may be easily connected to a first sensor part of the rotation angle sensor of the actuator. The actuator with the rotation angle sensor can particularly be used in motor vehicles.