To provide a laser light generating apparatus, a line light generation optical system, and a laser marking apparatus to optimize the apparent brightness of the line light at various irradiation distances.

The laser marking apparatus is provided with a distance measuring function for measuring irradiation distances, and the oscillation condition of a laser is controlled so that the apparent brightness of the line light becomes constant, according to irradiation distances. The apparent brightness of the line light is improved on the basis of the Broca-Sulzer effect, without changing the laser power of a light source.