A device for adjusting horological functions of a timepiece, including a mechanism for selection and actuation, including: a drive driving a driving pinion in the clockwise and anti-clockwise directions, a driven pinion driven when the driving pinion turns clockwise and anti-clockwise, the driven pinion moving into a first position by the driving pinion turning clockwise, in which the driven pinion actuates an actuator of a first horological function, and moving into a second position by the driving pinion turning anti-clockwise, in which second position, the driven pinion actuates an actuator of a second horological function, the driven pinion not actuating the actuator of the first horological function when it is in its second position, and vice versa. The mechanism for selection and actuation includes at least two driven pinions, and the adjusting device includes a control mechanism selectively bringing the driving pinion into engagement with each of the driven pinions.