Chronic constipation in infants and young children does not require colonoscopy if it is caused by poor diet, gastrointestinal dysfunction and so on. If it is caused by intestinal foreign bodies or tumors, enteroscopy or treatment is needed. Constipation in infants and young children is mostly caused by irrational diet or gastrointestinal dysfunction, which can be improved by drinking moderate amount of water, eating more celery, leeks, bananas, pears and other foods with high dietary fiber, massaging the abdomen, performing bowel training, and taking probiotics (such as bifidobacteria, clostridium casei, and so on) orally, and at this time, there is no need to undergo a colonoscopy. If the constipation of infants and young children can not be improved by the above methods, it is necessary to consider the existence of intestinal foreign bodies or tumors, and at this time can be subjected to enteroscopy or treatment. When infants and young children have dry stools and straining to pass stools, it is recommended to consult a specialist for evaluation or treatment.