To accelerate the scribing of a marking line and improve the efficiency of the scribing operation by preventing a clog of a through hole with smoke and dust by means of a smoke exhausting hole, minimize damage by breaking a brittle portion, and reduce production cost by permitting the replacement only of a needle element.

A laser scriber 23 has the through hole opening in the center of the needle element 42, and directs a laser beam along the through hole and emits it from a point of the needle element to scribe a marking line in a workpiece W with the laser beam. The needle element has the smoke exhausting holes in communication with the through hole, so that smoke stagnant in the through hole can be exhausted via the smoke exhausting holes. The needle element has the brittle portion 53, at which the needle element breaks apart when bending force of or above a constant level acts on the point of the needle element owing to, for example, contact of the point with the workpiece.