The invention relates to a method for determining the rotational speed of a motor vehicle wheel (4), which rotates about a rotational axis (2), by an acceleration sensor (10). The acceleration sensor (10) is mounted on the motor vehicle wheel (4) at a spacing (r) to the rotational axis (2) in such a manner that the force-sensitive axis of the acceleration sensor (10) is perpendicular to the rotational axis and is perpendicular to the centrifugal force which acts on the acceleration sensor (10) with a rotation of the motor vehicle wheel (4) about the rotational axis (2). The rotational speed of the motor vehicle wheel (4) is measured in that the rotational axis (2) is aligned horizontally so that a periodic measurement signal is generated in the acceleration sensor (10) by the gravitational force. The frequency of the measurement signal corresponds to the rotational speed of the motor vehicle wheel (4) about the rotational axis (2). The invention also relates to an air pressure control system in which the rotational speed of the motor vehicle wheel is measured.