To provide a laser igniting engine having optical fibers enabling a laser beam to be accurately transmitted to the laser beam incident parts of the optical fibers while accurately matching the laser beam with the emitting timings of the laser beam so that the emitting direction of the laser beam to the plurality of optical fibers can be freely controlled while matching it with the emitting timings of the laser beam from a laser oscillator.

This laser igniting engine comprises a plurality of optical fibers disposed so that their incident parts are set at pre-set positions, a mirror rotating device rotated in association with the rotation of an engine, a rotating mirror having a reflection surface for the laser beam from a laser oscillator formed by tilting it diagonally a prescribed angle relative to the rotating axis of the mirror rotating device and rotatingly driven by the mirror rotating device, and a mirror controller rotatingly controlling the mirror rotating device so that the laser beam after being reflected on the reflective surface of the rotating mirror is injected in order according to the rotation of the rotating mirror into the incident parts of the plurality of optical fibers.