A laser processing method includes a step of holding a film side of a workpiece which has been divided into chips and whose reverse side carries an adhesive film stuck thereto, a step of detecting widths of grooves in the workpiece at predetermined chip intervals and central coordinates of the widths of the grooves, a step of calculating laser beam irradiation lines based on the detected widths of the grooves and the detected central coordinates, a step of determining misalignment levels of the calculated laser beam irradiation lines according to misalignments of the grooves in widthwise directions thereof, and a step of processing the adhesive film with a laser beam by applying the laser beam to the adhesive film at bottoms of the grooves along the laser beam irradiation lines, thereby separating the adhesive film.