A lighting device includes: a first light source unit including a plurality of laser elements and emitting a first light flux in a first direction; a second light source unit including a plurality of laser elements and being arranged to emit a second light flux in the first direction and to be spaced apart from the first light source unit by a first distance in a second direction orthogonal to the first direction; and an optical path shift optical system including: a first reflecting surface that reflects the second light flux emitted from the second light source unit toward the first light flux; and a second reflecting surface that is parallel to the first reflecting surface and reflects the second light flux reflected by the first reflecting surface to be parallel to the first light flux at a second distance shorter than the first distance.