In the manufacture of cast product, various melt processing is carried out between melting of iron and pouring molten metal into a mold. We have been researching on casting technology for high-quality for cast aluminum and cast iron. Information in this report is as follows : 1.Effect of rear earth element on molten metal treatment of cast iron. 2.Effect of CE value and chemical composition on chilling of tin wall cast iron. 3.Holding of lecture on cast iron and rear earth element. 4.Grain refinement of Al-Si alloy by electromagnetic stirring.