Stomach cancer belongs to a kind of malignant tumor of digestive system, and one symptom of stomach cancer is black stool. Because it may be related to the bleeding of stomach cancer lesion, which leads to black stools, other gastrointestinal bleeding should be excluded as well. Black stool in gastric cancer needs to treat the primary lesion of gastric cancer, and if it can be treated surgically, usually it needs to do radical gastric cancer resection, including most of the stomach resection or total gastrectomy. After surgery, gastric cancer patients also need to do adjuvant chemotherapy, such as 4-6 courses of intravenous chemotherapy or intravenous chemotherapy combined with oral chemotherapy. In some gastric cancer patients with advanced lesions, metastasis to other parts of the body or patients who cannot tolerate chemotherapy, targeted drugs, such as oral apatinib, can also be considered. If there is more bleeding, it can also be treated with drugs to inhibit gastric acid and stop bleeding.