Bleeding from constant diarrhea may be caused by inflammatory bowel disease, intestinal cancer, acute gastroenteritis and other factors. 1. Inflammatory bowel disease: most of the inflammatory bowel disease is caused by the damage of intestinal mucosa due to bacterial infection, which will be accompanied by the phenomena of blood in the stool, mucus, pus and blood in the stool, and at the same time, it is accompanied by uninterrupted abdominal pain, which will cause the body to lose weight and other symptoms. 2. Intestinal cancer: colorectal cancer will cause incomplete obstruction of intestinal tract, which will lead to increased frequency of bowel movement, resulting in diarrhea, and will stimulate the rectum to produce blood. 3. Acute gastroenteritis: when patient’s diet is not clean and contaminated by bacteria, virus and other pathogenic microorganisms, it may lead to infection of gastrointestinal mucosa and cause acute gastroenteritis, which will make patient’s gastrointestinal peristaltic disorder, diarrhea, abdominal pain, nausea and vomiting, fever and other symptoms, and patient’s stool is not shaped, and sometimes may be accompanied with bloody stool. There are other reasons for diarrhea and bleeding, it is recommended to go to the hospital for examination, to clarify the cause of the disease and timely symptomatic treatment.