Complications of inflammatory bowel disease include gastrointestinal bleeding, intestinal perforation, colon cancer, primary sclerosing cholangitis, thrombosis, intestinal obstruction and malnutrition. 1. Gastrointestinal bleeding: due to the infiltration of the intestinal mucosa caused by inflammation, erosion, ulceration and bleeding occur. 2. Intestinal perforation: when the intestinal ulcer is deep, it may cause intestinal perforation leading to hemorrhage. 3. Colon cancer: the presence of serious damage to the intestinal mucosa and repeated attacks may easily induce cancer. 4. Primary sclerosing cholangitis: Inflammatory intestinal peripheral tissues and organs spread, causing inflammation in the bile ducts causing bile duct stenosis, and bile stasis inducing primary sclerosing catheterization. 5. Thrombosis: inflammatory bowel disease will also increase the risk of thrombosis, need to pay attention to monitoring coagulation function. 6. Bowel obstruction: The inflammation caused by inflammatory bowel disease can lead to bowel obstruction. Inflammatory bowel disease is recommended to consult the doctor and actively give treatment to avoid complications.