Abstract: objective: To investigate the application value of automatic injection of iodine with colonic imaging in children with colon and small intestine lesions. Methods: 55 cases of children with suspected lower gastrointestine lesions were collected in our hospital. All patients were diagnosed with colon and small intestine lesions by automatic injection of iodine colonic examination. Results: Automatic injection of iodine with colonic angiography showed the location of the lesion. The diagnosis was 5 cases of congenital jejunal stenosis, 10 cases of congenital jejunum atresia with small colon, 20 cases of congenital ileum atresia with small colon, 2 cases of congenital small intestine, and 4 cases of congenital anal atresia with rectal vaginal fistula. Congenital giant colon 12 cases, colon polyp 2 cases. Conclusion: Automatic injection of iodine colonic examination is simple, safe, fast and effective. It is not only the best method to diagnose children's colon and small intestine lesions, but also can reduce the radiation damage of children and their accompanying family members.