Amebic colitis was common disease in Korea as well as in the world especially frequent in tropical area such as Africa, India and South America. Clinicopathological forms of this condition were ulcerative rectocolitis(95%), typhloappendicitis (3%), ameboma(1.5%) and fulminating colitis with toxic megacolon(0.5%). The fulminatingamebic colitis with toxic megacolon was very rare and dangerous condition which was reported by Wruble on 1966.Toxic megacolon was seen in hte cases of ulcerative colitis, Crohn's disease, typhoid fever, cholera, and acutebacillary dysentery. Radiological findings of fulminating amebic colitis with toxic megacolon were megacolon, multiple polypoid filing defects, thumb printing, and cobble stone appearance, which were resemble with ulcerative colitis. The cause of toxic magacolon was not well known, but it has been speculated that this results from transmural disease with destruction of muscle and the myenteric plexus with resultant loss of muscle tone. Authors experienced a case of fulminating amebic colitis with toxic megacolon which was resemble with ulcerative colitisby radiologically at Kyung Hee University Hospital and reported it with review of the literatures.