Aiming at the development of Si solidification refining process with Si-Al melt, investigations on separation method of Si grains solidified from Si-Al melt and the laboratory scale refining test were carried out. By the use of electromagnetic force under the fixed alternating magnetic field, solidified Si grains were successfully agglomerated in the Si-Al alloy and the high Si density part was obtained, although the use of gravity force was not effective. Furthermore, the refining test with induction heating revealed the high purification ability of this refining.