Device for detecting the position of at least a first and a second hand of an electromechanical watch, said first and second hands moving above a dial, the detection device including a single light source emitting a light beam towards the first and second hands, and a first and a second light detection system, the light source and the first and second light detection systems being mounted on or underneath the dial, the light source and the first and second light detection systems being arranged so that, in a determined position of the first hand, the light beam emitted by the light source is reflected by the first hand towards the first detection system, and in a determined position of the second hand, the light beam emitted by the light source is reflected by the second hand towards the second detection system.