Disclosed is a method for producing a permanent magnet having Dy or Tb dispersed in the crystal grain boundary phase of a sintered magnet S. This method does not comprises a preliminary step for cleaning the surface of the sintered magnet before adhering Dy or Tb to the surface of the sintered magnet, and is thus improved in productivity. Specifically, an iron-boron-rare earth sintered magnet S isplaced in a process chamber (20) and heated to a certain temperature, while evaporating an evaporation material V which is placed in the same or a different process chamber and composed of a hydridecontaining at least one of Dy and Tb. The vaporized evaporation material is adhered to the surface of the sintered magnet, and metal atoms of Dy and/or Tb in the adhering evaporation material are dispersed into the crystal grain boundary phase of the sintered magnet.