Any blood from the stool, or blood mixed with stool, or blood before and after the stool, or simply blood, are called blood in the stool, it is a common symptom, can occur in the course of a variety of diseases. Some are even the precursors of serious diseases; repeated bleeding can cause anemia; more bleeding can cause shock, or even life-threatening. Therefore, blood in the stool should not be ignored and should be treated promptly by identifying the cause. Clinically, according to the amount of blood in the stool, it is divided into occult blood in the stool and visible blood in the stool, and according to the bleeding site, it is divided into upper gastrointestinal bleeding and lower gastrointestinal bleeding. There are many causes of blood in stool, and they are divided into upper gastrointestinal tract diseases, lower gastrointestinal tract diseases, and systemic diseases according to the primary disease causing the bleeding. In Chinese medicine, blood in stool is referred to as “blood in stool”, “lower blood”, “diarrhea blood”, “yin knot”, etc. According to the location of bleeding, there are distant blood and near blood. According to the location of bleeding, there are different distant blood, near blood, according to the blood color is fresh and cloudy, and there are intestinal wind, dirty poison. The etiology and pathogenesis of blood in stool have been described in detail in successive medical books. The Nei Jing points out that the main pathogenesis of blood in stool is the knotting of yin and the damage of yin liao; the Jin Kui Yao points out that the identification of blood in stool should be divided into distant blood and near blood, and at the same time proposes different treatment prescriptions according to its different pathological properties; the Treatise on the Origin of Various Diseases considers blood in stool to be injured by the five organs, with the distinction between hot and cold; the Ji Sheng Fang firstly divides blood in stool into “blood in stool” and “intestinal wind and dirty poison”. In the Treatment of Blood in Stool, the treatment principle of “Disperse the wind, clear the heat, warm the cold, and tonic the deficiency” is proposed; “Danxi Xinfa” proposes that the location of the disease is “only in the stomach and large intestine The “Danxi Xinfa” proposes the treatment principle that the location of this disease is “only in the stomach and large intestine” and “where blood medicine is used, it should not be used in a single line to stop it”; the “Essentials of the Treatment” uses the presence or absence of shortness of breath as the key point of differentiation between blood in stool and dysentery; the “Introduction to Medicine” divides blood in stool into intestinal wind, dirty poison and yin knot, and considers that the causes of the three are different and the clinical manifestations are also different; the “Jing Yue Quanshu” also talks about The “Introduction to Medicine” classifies blood in stool into intestinal wind, dirty poison and yin knot, and considers that the causes of these three diseases are different and their clinical manifestations are also different; “Jing Yue Quan Shu” also talks about the differentiation between blood in stool and intestinal Y (dysentery), and clearly points out the parts of distant blood and near blood; “Zhi Zhi Hui Tiao” considers pure blood in the lower part of the body, bright red blood as heat, dark color as cold and black color as silt, which has some clinical guidance. The etiology and pathogenesis of blood in stool is mainly due to dietary indiscretion, feeling of external evil, emotional and mental disorders, and deficiency of the body after a long illness. The main pathogenesis is fire and heat, damage to the gastrointestinal vessels and ligaments, or deficiency of middle energy, deficiency of cold in the spleen and stomach, loss of blood control and overflow into the intestines, resulting in blood in the stool. The initial disease is mostly real, but the disease becomes deficient after a long time. Because dysentery, blood in stool and hemorrhoids are all manifested by blood in stool, attention should be paid to differentiation: dysentery is accompanied by pus and blood, abdominal pain, shortness of breath and burning in the anus, while hemorrhoids are bright red blood in stool, often accompanied by pain in the anus during stool, and are not difficult to differentiate by finger diagnosis. In addition, when the upper gastrointestinal bleeding is large, the stool can be dark red or even bright red, similar to the lower gastrointestinal bleeding, on the contrary, the jejunum and ileum bleeding is not large, in the intestinal tract for a long time, can appear black feces, similar to the upper gastrointestinal bleeding. In the treatment of blood in stool, the first thing to do is to stop the bleeding, but different treatments should be implemented according to different pathologies. The first step is to identify the color and nature of the blood in the stool, and then to identify the hot and cold nature of the disease. The treatment should be based on the evidence. For heat accumulation in the stomach, it is advisable to clear the stomach and fire, remove blood stasis and stop bleeding; for heat stagnation in the liver and stomach, it is advisable to clear the liver and fire, cool the blood and stop bleeding; for blood stasis with qi stagnation, it is advisable to move the qi to relieve depression, activate the blood and remove blood stasis; for internal heat toxicity, it is advisable to clear heat and detoxify the toxin, cool the blood and stop bleeding; for dampness and heat vaporization, it is advisable to clear heat and remove dampness, cool the blood and stop bleeding; for deficiency of middle energy, it is advisable to benefit the qi and strengthen the spleen, nourish the blood and stop bleeding; for deficiency of spleen and stomach, it is advisable to warm the yang and strengthen the spleen, strengthen the yin and stop bleeding. While treating, attention should be paid to dietary regimen, avoiding emotional stimulation, proper rest, and in patients with more blood in the stool, the condition should be closely observed for palpitations, sudden pallor, and fine pulse count to prevent deficiency. Diet should be light and easy to digest, eat less and more meals, avoid tobacco, alcohol and spicy sting.