Abstract: The effects of rare earth on magnesium alloys are summarized in terms of anti-oxidation, hydrogen removal, fluidity, crystal grain refining and consolidation etc. The latest development trend and achievements of rare earth magnesium interalloys, cast, wrought, and RSP (rapid solidification processing) magnesium alloys are summed up, and the great potential in non-crystal magnesium alloy development and superplasticity study of magnesium alloy are generally introduced in this paper. The promising application will induce significant innovation in structural material field