Etiology: Chronic inflammation of the appendiceal wall layer, fibrous tissue hyperplasia, and thickening of the wall narrow or occlude the appendiceal lumen, preventing appendiceal emptying and compressing the nerves in the appendiceal wall to produce pain. It can be transformed from acute appendicitis, or it can start as a chronic process. Clinical manifestations: frequent vague pain or discomfort in the right lower abdomen, the pain is not severe or typical, and acute attacks can be triggered by strenuous activity or dietary disorders. It may also manifest as repeated episodes of acute appendicitis. Signs: limited deep pressure pain in the right lower abdomen at the McDonald’s point, the pressure pain is often present and fixed. Blood picture: leukocytes are usually within the normal range, but acute attacks may present with elevated leukocytes. Auxiliary examination: barium enema examination (BE), if the appendix is seen to be stiff and in a more fixed position, or the appendix is not visualized or incompletely filled, or the appendiceal cavity is irregular and narrow, and there is barium residue in the appendiceal cavity on fluoroscopy after 72 hours, chronic appendicitis can be diagnosed. Treatment: If the diagnosis is clear that there is an indication for surgery, surgical resection and pathological examination are recommended.