The invention relates to a lighting device (1) for a motor vehicle. The device comprises: a wall having at least one protuberance (2); and at least a first light source located inside of said protrusion. The wall has a reflective area (3) having light reflection properties, and is arranged facing the first light source so that the first light source is adapted to generate a light beam passing through the wall, spreading the outside of the lighting device before being reflected onto the reflective zone of the wall to generate a visible light from the wall.