Abstract: The characteristic of the morphology and structure of the typical graphite (flake, spheroidal vermicular) in cast iron have been investigated with scanning electron microscopy (SEM). The observation on the specimens which had been treated with deep etching and thermal oxidation etching was carried out and the results were obtained as follows;1.The various classes of the flake graphite (Classes-4, B, C, D) were consisted of flakes that were branchecd and interconnected. So that they belong to the same type of graphite Growth of them occurred primarily on fhe [1010] direction, and was inhibited on the [0001] direction, it follows that fhe flake graphite was formed.2.The spheroidal graphite may be obtained in cast iron treated with commercially pure magnesium, yttrium or cerium as well as industrially nodulizing agents. The formations of the spheroidal graphite in cast iron treated with one of them was different. The surface of the spheroidal graphite obtained with magnesium is more smooth and rounded than that with yttrium and cerium. And the surface of the spheroidal graphite obtained with the industrially nodulizing agents is intermediated between the two kinds of form of the graphite.It was observed in the thermal oxidation etching specimen that there are annualring structure in the spheroidal graphite. It was shown that the surface of the spheroidal graphite was (0001) plane of the graphit crystalline. And its growth was carried on from the center of it, and was along to the 00001] direction.3. The vermicular graphite was a intermediate morphology between the flake and spheroidal They connected each other in same eutectic cello The mode of growth of the vermicular graphite was intermediate between the flake and spheroidal also.