The GI tract is divided into upper and lower GI tracts, where the upper GI tract includes the oral cavity, esophagus, and stomach, and the lower GI tract includes the large and small intestines. Gastrointestinal bleeding is defined as bleeding from the gastrointestinal tract due to some irritation or stressful condition. Most lower GI bleeding is associated with parasitic infections, other infections, anal fissures, anal fistulas, rectal or small intestinal disorders, etc. Upper GI bleeding is associated with gastritis, gastric ulcers, or ulcers with perforation, occupational lesions of the esophagus, esophageal hiatal hernia, esophagitis, etc. GI bleeding can be caused by inflammation of the GI tract itself, mechanical injury from outside, its own vascular lesions, or tumor occupational lesions. Gastrointestinal bleeding can be caused by a variety of factors such as inflammation of the GI tract, external mechanical injury, vascular lesions, or tumor-occupying lesions, and can also be triggered by lesions in neighboring organs, and can be associated with systemic diseases, such as stress reactions or systemic diseases that involve the GI tract, resulting in GI bleeding. Therefore, gastrointestinal bleeding is usually associated with self-inflammatory or occupying lesions or other adjacent organ diseases that infest the digestive system and cause digestive bleeding, or even systemic diseases that cause stressful bleeding in the digestive tract.