The color of the stool appears black and with blood, may be due to these factors: 1, digestive diseases, digestive diseases can easily cause black stool, such as varicose vein rupture of the fundus of the stomach or esophagus, intussusception, easy to cause black stool, resulting in defecation with blood. 2, due to diet, in addition to gastrointestinal diseases can lead to black stool, blood, consumption of certain foods can cause black stool, such as chicken blood, duck blood or consumption of large amounts of beef, can cause iron in food to form iron sulfide, resulting in black stool. 3, blood diseases, blood diseases in the body can also lead to iron sulfide, resulting in food. Black stool, such as chicken blood, duck blood or consume a lot of beef, will cause the iron in the food in the human body to form iron sulfide, resulting in black stool. 3, blood diseases, blood diseases in the body can also cause blood, black stool, such as neonatal hemorrhagic disease, hemophilia, easy to cause the bowel movement with blood, black.