A laser processing apparatus includes a placement base on which a workpiece is placed, a beam shaping optical system that shapes laser light such that a first laser light irradiated region of a mask blocking part of the laser light has a rectangular shape having short edges and long edges, the beam shaping optical system capable of causing one of a first radiation width of the first irradiated region in the direction parallel to the short edges and a second radiation width of the first irradiated region in the direction parallel to the long edges to be fixed and causing the other to be changed, a projection optical system that projects a pattern on the mask onto the workpiece, and a mover that moves the first irradiated region at least in the direction parallel to the short edges to move a second laser light irradiated region of the workpiece.