A hemorrhoid is the most common cause of acute lower gastrointestinal (LGI) bleeding. Diverticulosis, angiodysplasia and ischemic colitis can also cause LGI bleeding. Acute LGI bleeding from the appendix is very rare. We experienced a case of a 33‐year‐old woman with acute LGI bleeding from the appendix. Colonoscopy demonstrated an active hemorrhage from the orifice of the appendix. The patient was treated with a appendectomy, and a histological examination showed the presence of a small ulcer with inflamed granulation tissue in the mucosa and submucosa. (Korean J Gastrointest Endosc 2008;36: 173-176)