Black stool in 6-month-old babies is mostly related to excessive intake of iron, and in a few cases it may also be caused by constipation or gastrointestinal bleeding. Parents should promptly take their children to the hospital to identify the cause, targeted treatment, so as not to delay the disease. Common causes 1, too much intake of iron: babies eat iron-containing foods, such as animal liver, animal blood, rice flour, milk powder, or too much iron supplements, the body can not absorb iron in time, it is easy to lead to black stools; 2, constipation: when babies have constipation symptoms, the stool is too dry, stay in the intestines for too long, the color becomes dark, manifested as black stools; 3, gastrointestinal bleeding: Inflammation of the digestive tract or the presence of local mucosal damage may lead to bleeding, blood oxidation in the digestive tract, thus causing black stools. Treatment 1, baby constipation, parents can moderate the baby abdominal heat compress or massage, under the guidance of the doctor, give the baby lactulose to soften the stool, regulate the intestinal flora, can also be used externally open plug to relieve constipation; 2, baby gastrointestinal bleeding, should first rehydration treatment, give gastrointestinal decompression, out of the danger period for arteriography, enteroscopy, gastroscopy, to clarify the cause and The cause and location of the bleeding should be clarified, and plasma or blood transfusion should be given to treat the bleeding. Note 1: Parents should pay attention to feeding their children iron-containing foods or iron supplements in moderation, and give the baby more water, vegetable juice or fruit juice to promote intestinal peristalsis and prevent constipation; 2: Pay attention to keeping the baby warm and keep the air circulating in the living environment to avoid getting cold.