This laser beam processing apparatus includes a fiber laser oscillator, a laser beam branching unit, a laser beam injecting unit, a fiber transmission system, a laser beam irradiating unit, and a processing table. Based on a fiber laser beam, which is oscillation-outputted from the fiber laser oscillator, the laser beam branching unit executes simultaneous multi-branching from the fiber laser beam into a plurality of branched laser beams. The laser beam injecting unit injects the branched laser beams respectively into optical fibers for transmission and the laser beam irradiating units condense and apply the branched laser beams from the optical fibers for transmission respectively to processing points.