The main reasons for stomach pain after stool are as follows: 1, may be the inflammation of the intestinal mucosa or tumor, stool on the intestinal mucosa of the inflammation or tumor caused by the stimulation, will cause the symptoms of stomach pain after stool, you need to timely examination, symptomatic treatment. 2, caused by overeating or unclean diet, the gastrointestinal mucosa by the stimulation of the food, triggered by acute gastroenteritis, the patient can recover as long as pay attention to the diet, a little rest. The patient can recover by paying attention to diet and resting a little, and if the symptoms are serious, he can take some medicines to relieve them.3, it may be intestinal spasm, the smooth muscle of the intestinal tract is stimulated after bowel movement will induce intestinal spasm, which will be manifested as paroxysmal pain, and most of intestinal spasms can be recovered on their own, but if the symptom of tummy ache is very serious, it is necessary to seek medical treatment in time.4, gastrointestinal dysfunction, reduced digestive function, will also appear the symptom of tummy ache.