Abstract: Through the optical microscope, based on the practice of 6 463 aluminium alloy production, with 6 463 aluminium alloy under the same casting process condition, the genetic effect of raw material containing silicon phase on casting of aluminium alloy on the morphology of Mg₂Si phase in the aluminium alloy casting using Al-Si intermediate alloy with different structures in the casting production is studied. It provides the basis for optimization for 6 463 aluminium alloy casting production and guidance for subsequent processing of 6 463 aluminium alloy. The results show that the organization of hereditary Al-Si intermediate alloy which has not been damaged in the casting process, will affect the casting pattern and distribution of aluminum alloy containing silicon phase Mg₂Si. In order to avoid the effect of surface quality of coarse Mg₂Si relative profiles, Al-Si intermediate alloy of fine microstructure should be used in casting production.