So far, the cause of congenital megacolon is not very clear, most people are more recognized there are so many factors: 1, the family genetic factors, that is, genetic problems; 2, environmental factors, together. Comprehensively speaking, it is the family congenital factors, coupled with the intervention of the surrounding environment, resulting in the embryonic period, we know that the embryonic period of 6-12 weeks, is the embryonic intestinal nerve migration into a stage. At this stage, if the nerve migration process is impeded or abnormal, resulting in the cessation of nerve migration, the distal mesentery will lack nerves, which is called neurodegeneration. It is more common to see nerve agenesis in the colon or a part of the colon, such as the sigmoid colon, the rectum, and up to the anus, resulting in mechanical intestinal obstruction due to the lack of diastolic ability of the intestinal tubes in this part of the intestine, which is in a state of prolonged and continuous spasm, resulting in the inability of the intestinal tubes to diastolic, resulting in a mechanical intestinal obstruction. As a result, the child will have long-term abdominal distension, vomiting, nausea and decreased bowel movement, which is what we call congenital megacolon.