Provided is a method for manufacturing a rare-earth magnet, the method comprising the steps of preparing a rare-earth magnet powder including R, Fe and B as composition components, wherein, R is at least one element selected from among the rare earth elements including Y and Sc; mixing a heavy rare-earth compound including a heavy rare-earth hydride with the rare-earth magnet powder; molding the powder mixture in a magnetic-field; and sintering and performing heavy rare-earth diffusion at the same time.