Two different white cast irons alloyed with Mo, W and Cr(or V) were prepared in order study their solidification behavior during thermal analysis. The specimens were produced using a 15kg-capacity silica lined high frequency induction furnace. Melts were super-heated to 1600도씨, and poured at 1550도씨 into Y-block pepset molds. Two combinations of the alloying elements were selected so as to obtain different types of carbide structure : 3%C-10% Cr-5% Mo-5%W(alloy No. 1) and 3%C-10%V-5%Mo-5%W(alloy No. 2). To clarify the solidification sequence, each iron(50g) was remelted at 1450도씨 in an alumina crucible using a silicon carbide resistance furnace under the argon atmosphere. The molten iron was cooled at the rate of 10도씨 / min and quenched into water from six different temperatures during thermal analysis. The solidifacation structures were found to consist of primary austente, (austenite _ M7 C3)eutectic and (austenite + M6C)eutecic in the alloy No. 1 and primary MC, (austenite + MC)eutectic and (austenite + M2C)eutectic in the alloy No. 2.