To obtain a laser beam quenching method for a turbine shaft by which the development of a product is performed by realizing the improvement of durability with a laser beam quenching to the turbine shaft for turbo-charger.

In the laser beam quenching method for the turbine shaft for laser beam quenching to the shaft end part and the shaft intermediate part by performing the laser beam irradiation under using kaleidoscope to the shaft end part A and the shaft intermediate part B at an impeller side while rotating the shaft for turbo-charger; the laser beam quenching method for the turbine shaft is satisfied to the following conditions, that is, the shaft part A is applied to 3.0 KW laser beam power, 1.4-1.8 sec irradiating time and 1 rps rotating speed, and in the other part, the shaft intermediate part B is applied to 2.75 KW laser beam power, 1.6-1.8 sec irradiating time and 2 rps rotating speed.