To provide a laser processing apparatus which avoids surface contamination caused by processing decomposition product (debris) generated during laser processing.

Two pairs of gas ports 21 to 24 arranged parallel to a moving direction of an XY stage 1 are stacked in an optical axis direction of a laser beam. Gas is jetted from the gas ports 21 and 22 on a lower layer side toward a processing point of the laser beam, the gas is sucked by the gas port 24 on a side of the moving direction of the stage among the gas ports 23 to 24 on an upper layer side, and the gas port 23 facing the gas port 24 jets the gas to the processing point. A high pressure part formed at a surface of a work-piece is shifted to the moving direction of the XY stage 1, and debris generated by laser processing is sucked and recovered by using a wall of the high pressure part.