A simultaneous laser welding apparatus of a vehicle light comprising a placement support for a container body and a lenticular body of a vehicle light welded together at reciprocal perimeter profiles, a plurality of laser sources, a plurality of optical fibres associated with the laser sources at input ends for transmitting the light beams, a fibre-holder support device for blocking output ends of the optical fibres in predetermined positions, spaced apart by a pitch, a light guide provided with at least one seat which receives the light beams coming from the output ends of the optical fibres, to a light output wall which sends the light beams towards the welding interface. A single optical fibre is associated with each laser source.