In the view point of the environmental conservation and the energy reduction, the recycling of metal scrap is coming as one of the global subjects in the world. In this study, the formation and morphological change of the intermetallic compounds in the scrap of Al-Si-Cu alloy(JIS ADC12), which were widely used in diecasting process, was investigated in order to eliminate the Fe element, which was usually accumulated in the scrap. In accordance, the formation and morphological change of Fe-contained intermetallics by addition of Mn in Al-Si-Cu system alloy was investigated with the amount of Mn added, holding time and holding temperature. The formation temperature of the large angular intermetallic compound ascended with the amount of Mn added. The shape of needle-like Al_5FeSi compounds were completely changed to that of large angular Al_(15)(Fe,Mn)₃Si_5 intermetallics when Mn/Fe ratio was higher than 3/4. The higher Mn/Fe ratio was, the larger angular Al_(15)(Fe,Mn)₃Si_5 intermetallics were formed and the larger those were. Therefore, the content of Fe in matrix decreased from 1.64wt.% to 1.1wt.%. (Received November 29, 1997)