Vague pain in the lower right side of the stomach is seen for the following reasons: First, there is a previous history of acute appendicitis, and after effective anti-infection treatment, the symptoms improve and local adhesions are left behind. After overeating or catching a cold, it is easy to trigger an attack of appendicitis, which is manifested as pain in the right lower abdomen, also accompanied by nausea and vomiting, and even fever. Anti-infection treatment can improve the symptoms, and if necessary, surgery is also an option. Secondly, for middle-aged and elderly patients, if there is vague pain in the right lower abdomen, accompanied by loss of appetite and weight loss, it is considered to be caused by malignant tumor of the intestine. It may be accompanied by changes in bowel habits, black stools, significant abdominal distension after eating, and vague pain in the right lower abdomen. Fibrous colonoscopy can clarify the diagnosis, and early diagnosis can be confirmed for timely radical resection surgery.