Rectal cancer is the most common malignant tumor in the gastrointestinal tract after stomach and esophageal cancer (about 65%). Currently, it has jumped to the second place in the list of cancers, but its cause is not completely clear, so there is no special prevention method until now. The preventive measures listed below are mainly to reduce the chance of cancer and early detection and treatment of patients. 1, actively prevent and treat rectal polyps, anal fistula, anal fissure, ulcerative colitis and chronic intestinal inflammation; for multiple polyps, papillary polyps, once the diagnosis is clear, early surgery should be removed to reduce the chance of cancer. 2.Diversify diet, develop good eating habits, do not be partial or picky, do not consume high-fat and high-protein diet for a long time, and often eat fresh vegetables containing vitamins and fiber, which may play an important role in cancer prevention. 3.Prevent constipation and keep the bowel movement smooth. 4. Pay great attention to regular cancer screening and self-examination at all times to enhance vigilance. After discovering “warning signals”, timely diagnosis and treatment can be carried out to achieve early detection and early treatment in order to improve the survival rate of rectal cancer.