A laser groove machining method for forming bottomed grooves in a surface of a workpiece using a laser, wherein an emitting position of a laser beam which is to be emitted onto the workpiece is shifted relatively along groove forming positions at a high speed of 150 mm/min. or faster. Thus, melted portions which are melted by the laser beam can easily be separated, cooled and removed by shifting the laser beam emitting position at high speed. In addition, water may be jetted to the workpiece so as to form a pillar of water so that the laser beam is emitted through the interior of the pillar of water so formed.