The invention discloses a high-speed laser out-of-focus quenching strengthening method for micro shaving tools. Laser light spots are enlarged to widths of blades by using the scattering characteristics of laser after the laser is out of focus; proper focal distances of field lenses are selected according to quenching depths needed by the blades; and laser is output according to paths by using high-speed galvanometers for finishing quenching of workpieces at a time. The method has the characteristics of being free of repeated focusing, high in quenching speed, good in strengthening effect, considerable in performance and economical benefit and the like.