Abstract: The modification and refinement of microstructure are the key effects of property improvement of A356 cast aluminum alloy.The recent research results show that La as a single modifier or combined addition with other elements as a compound modifier to modify A356 alloy were summarized.It is shown that La and other rare earth elements have obvious modification effects on A356 alloy, and the optimum mass percent, related technologies and mechanisms of La as the main modifier were discussed.