To provide a method for marking with laser beam, by which a purchas er of a jewel such as a diamond can obtain a feeling of the highest satisfaction that the purchaser owns the jewels which is the only one in the world and of the greatest customer's satisfaction.

The relative position of a laser beam output part 20 and a transparent or translucent goods 10 is determined by a positioning part 30 in a way that a laser beam outputted from the laser beam output part 20 is focused at a position inside the arbitrary surface of the transparent or translucent goods 10 with a depth of a predetermined distance, and digital information for marking is generated in a marking data generation part 40. The laser beam output part 20 is operated by a laser bream control part 50 according to the generated marking data, and the digital information is marked on the focused part of the goods 10 with the laser beam by irradiating the part of the goods 10 with the pulse of the outputted laser beam.