Abstract: According to the further study of the rare earth lifting permanent magnet and the summary of the industrial prototypes,a systematic design theory has been established in this paper.Two regulations of the design of magnetic circuit are discussed,one is that the lifting permanent magnets beginning work point should lie on the point of the maximum magnetic energy product or a bit lower than that in the degenerative magnet curve,so as to raise the lifting ratio(the weight of attracted body/the weight of permanent magnetic bodies);the other is that the different performance permanent magnetic bodies should adapt to different kinds of magnetic circuits to low the cost ratio(the cost of permanent magnetic bodies/the weight of attracted body).

Key words: the rare earth lifting permanent magnet, maximum magnetic energy product, lifting ratio, cost ratio