The mechanism of abdominal pain in acute appendicitis includes several aspects, firstly due to the induction of several factors, such as the formation of fecal stones in the gastrointestinal tract in case of gastrointestinal dysfunction. Secondly, local anatomical factors of the appendix, including appendiceal curvature, elongation, or incomplete closure of the ileocecal valve. In addition, there are other factors such as viral infections that attack the appendix, such as viruses from the gastrointestinal tract or viruses and bacteria from the upper respiratory tract, which cause congestion and mild inflammation of the appendix, causing painful paroxysmal involvement around the umbilicus. Gradually, with the passage of time, the local inflammation of the appendix increases, forming a situation of purulent local exudation, or pain caused by omental encapsulation, swelling of the appendix, and thickening of the canal diameter, with the migration of the right lower abdomen forming a persistent pain. If, after waiting for a period of time, the localized appendix suppurates or even perforates, forming a confined peritonitis, it causes persistent and severe pain in the right lower abdomen. With the gradual increase of exudation, when a large amount of fluid accumulates in the abdominopelvic cavity, diffuse peritonitis will form, with significant pressure pain and rebound pain throughout the whole abdomen. Eventually, due to the encapsulation of the omentum, multiple abscesses in the pelvic and abdominal cavities are formed, causing limited pressure pain. All of the above are mechanisms of abdominal pain in appendicitis.