There are several common causes of stomach pain and wanting to defecate: first, acute enteritis, often caused by eating unclean food, will be accompanied by abdominal pain, watery stools. After defecation, this abdominal pain can be reduced or relieved, serious patients, may be accompanied by fever; second, ulcerative colitis, this abdominal pain and want to defecate will lead to pus and blood stool, wasting and other symptoms; third, functional gastrointestinal disease, itself no organic lesions, due to the function of the pain, want to defecate symptoms, may also be accompanied by diarrhea, constipation alternating symptoms. In addition, some intestinal polyps, malignant tumors, etc., may also lead to abdominal pain and want to defecate, after the discovery, it is best to do colonoscopy to investigate.