Three different multi-component white cast irons alloyed with Cr, V, Mo and W were prepared in order to study their as-cast and solidification structures. Three combinations of the alloying elements were selected so as to obtain the different types of carbides and matrix structures : 3%C-10%Cr-5%Mo-5%W(alloy No.1), 3%C-10%V-5% Mo-5%W(alloy No. 2) and 3%C-17%Cr-3% V(alloy No.3). The as-cast microstructures were investigated with optical and scanning electron microscopes. There existed two different types of carbides, M 7 C 3 carbide with rod-like morphology and M 6 C carbide with fishbone-like one, and matrix in the alloy No. 1. The alloy No. 2 consisted of MC carbide with chunky and flaky type and needle-like M 2 C carbide, and matrix. The chunky type referred to primary MC carbide and the flaky one to eutectic MC carbide. The morphology of the alloy No. 3 represented a typical hypo-eutectic high chromium white cast iron composed of rod-like M 7 C 3 carbide which is very sensitive to heat flow direction and matrix. To clarify the solidification sequence, each iron(50g) was remelted at 1723K in an alumina crucible using a silicon carbide resistance furnace under argon atmosphere. The molten iron was cooled at the rate of 10K/min and quenched into water at several temperatures during thermal analysis. The solidification structures of the specimen were found to consist of austenite dendrite( γ ), (γ+M 7 C 3 ) eutectic and (γ+M 6 C) eutectic in the alloy No. 1, proeutectic MC, austenite dendrite( γ ), ( γ +MC) eutectic and (γ+M 2 C) eutectic in the alloy No. 2, and proeutectic M 7 C 3 and (γ+M 7 C 3 ) eutectic in the alloy No 3. respectively.