Beam delivery system may include one of a plurality of beam adjusting unit and a pulse laser beam outputted from the first beam adjusting unit of the most downstream of the plurality of beam adjusting unit for adjusting a divergence angle of the pulsed laser beam outputted from the laser device comprising a beam sampler for splitting part as a sample beam, a beam monitor for outputting the monitor size by receiving the sample light, a beam transmission control unit for controlling a plurality of beam adjusting unit based on the monitor size, a beam transmission control unit, so that the monitor diameter by the beam monitor is a predetermined value corresponding to a plurality of beam adjusting unit other than the first beam control, a plurality of beam adjusting unit other than the first beam adjusting unit from the upstream side sequentially adjusting the pulse laser beam may be adjusted first beam adjuster so as to condense downstream from the target position.