A method for continuous and efficient casting roll of magnesium alloy plates including providing plural induction furnaces, resistance furnace, casting roll and rollers; adding metal elements into the induction furnaces, the metal elements comprising Mg ingots or Mg alloy, the metal elements being smelted in the induction furnaces and then flow into the resistance furnace; controlling temperature of the Mg melt in the resistance furnace, wherein there are at least two temperature controlling areas communicated with each other, and a difference of temperatures is constant; transferring the Mg melt into biting area through a transferring pipe and modeling the mg melt into Mg plate, the temperature of the Mg melt into the biting area being 690±10° C.; Rolling the Mg plate in the rollers and each band of the rollers having a working temperature 250˜350° C., and the difference of temperature is ±10° C.