Acute appendicitis is at the top of the list when the reasons of acute abdomen are listed. Appendectomy is the most commenly performed surgical procedure worldwide. Stump appendicitis is one of the rarely seen complications after appendectomy. It was first described by Dr. Rosein 1945. Stump appendicitis is a clinical condition characterized by the inflammation of remnant appendix after incomplete appendectomy. The clinical picture resembles the reasons causing acute abdomen. Abdominal CT has an important role in diagnosis as well as history taking and physical examination. In patients admitting to emergency department with acute abdomen who has previous appendectomy history, stump appendicitis must be considered in the differential diagnosis, especially when the pain is present at right lower quadrant.