Combining with alloying and cast-rolling method,rare earth elements La and Ce were added into AZ series magnesium to fabricate magnesium sheet with high tensile strength and low cost.The microstructure of the Mg alloy sheet was observed by OM and SEM.The results reveal that fine rare earth phases are distributed uniformly in the matrix,and tensile strength can reach 376 MPa.And then,compared with the cast-rolling sheet with cast magnesium alloy produced by slow cooling,the results show that rapid cooling exhibits the higher refined grain effect.