Laser processing method

This method is provided with: a first step for preparing an workpiece; a second step for directing a laser beam at a first laminar member along a planned-processing line to form a modified region on the first laminar member along the planned-processing line, the front surface of the workpiece being the surface to be irradiated with the laser beam; a third step for directing the laser beam at a joining layer along the planned-processing line to form a processing mark on the joining layer along the planned-processing line, the front surface of the workpiece being the surface to be irradiated with the laser beam; and a fourth step for directing the laser beam at a second laminar member along the planned-processing line to form a modified region on the second laminar member along the planned-processing line, the rear surface of the workpiece being the surface to be irradiated with the laser beam. In the fourth step, which follows the first through third steps, the processing mark formed on the joining layer is used as an index to align the position where the laser beam is directed on the second laminar member.