Direct chill (DC) casting is currently the most common casting practice employed in industry for Al alloys. In this study, an intermediate frequency electromagnetic (IFEM) field was applied during DC casting of Al-8 wt.%Si alloy. The results show that compared to conventional casting, the alloys processed under IFEM field exhibit superior refinement in the microstructure as well as enhancement of the mechanical properties. In addition, these improvements become more pronounced when the current is increased. The role of IFEM field in inducing forced convection, and the subsequent phenomena, such as achievement of a uniform temperature field, fragmentation of the developed dendrites and the promotion of their equiaxed growth during solidification, could be confirmed by experimental observations.