消化道出血（英语：gastrointestinal bleed (GI bleed)、gastrointestinal hemorrhage）是咽至直肠之间任何部位的消化道出血。消化道出血有多种成因，该病的主要形式可以经由病史及身体检查区别。出血的程度有小至几乎探测不到，也有大至急性大量出血及危及生命者。

消化道以屈式韧带为界，其上为上消化道出血，其下为下消化道出血，消化道短时间内大量出血称为急性大量出血。

Gastrointestinal bleeding (GI bleed), also known as gastrointestinal hemorrhage, is all forms of bleeding in the gastrointestinal tract, from the mouth to the rectum. When there is significant blood loss over a short time, symptoms may include vomiting red blood, vomiting black blood, bloody stool, or black stool. Small amounts of bleeding over a long time may cause iron-deficiency anemia resulting in feeling tired or heart-related chest pain. Other symptoms may include abdominal pain, shortness of breath, pale skin, or passing out. Sometimes in those with small amounts of bleeding no symptoms may be present.