Helicobacter pylori is the focus of academic research and hot spots in recent years, the latest research found that Helicobacter pylori has a close relationship with the occurrence of certain hematologic diseases, which has a certain reminder of the significance of the treatment of these diseases. 1, Helicobacter pylori infection and unexplained iron deficiency anemia Helicobacter pylori infection is associated with anemia, especially unexplained iron deficiency anemia. It was found that the rate of H. pylori infection was significantly higher in patients with anemia than in those without infection, and the rate of H. pylori infection was higher in patients with moderate iron deficiency anemia compared with those with mild or moderate iron deficiency anemia. The mechanisms by which H. pylori causes iron deficiency anemia include: the growth and reproduction of H. pylori consume iron, leading to an increase in the body’s need for iron; H. pylori reduces gastric acid secretion and vitamin C concentration, which reduces intestinal absorption of iron, leading to the development of iron deficiency anemia; H. pylori infection increases permeability of the epithelial cells of the gastric and duodenal mucosa, which leads to the loss of iron and iron-containing proteins from the gastric and duodenal mucosa; and the H. pylori infection causes the loss of iron from the mucosa of the gastric and duodenal mucosa. The loss of iron and iron-containing proteins from the gastric and duodenal mucosa is caused by increased permeability of the gastric and duodenal mucosal epithelial cells due to H. pylori infection. 2.Helicobacter pylori infection and megaloblastic anemia Helicobacter pylori infection can induce body-specific humoral immunity and cellular immunity, making the gastric mucosal cell damage, causing chronic atrophic gastritis, leading to damage to the mural cells, reducing the secretion of pepsin, endogenous factors and gastric acid, affecting the absorption of vitamin B12 in the food, leading to megaloblastic anemia. 3, Helicobacter pylori infection and idiopathic thrombocytopenic purpura Many studies have found that after the eradication of Helicobacter pylori, some patients with idiopathic thrombocytopenic purpura have a significant increase in platelet counts, accompanied by a decrease in serum platelet-associated antibody IgG levels, suggesting that Helicobacter pylori infection may be one of the causative factors in some patients with idiopathic thrombocytopenic purpura. The possible pathogenesis is as follows: immune disorders, it is believed that the occurrence of idiopathic thrombocytopenic purpura due to Helicobacter pylori infection is related to Th1/Th2 immune dysregulation; Helicobacter pylori cytotoxin-associated gene A protein cross-reacts with platelet antigens; and the host genetic factors human leukocyte antigen class II system is related to the role of urease B in Helicobacter pylori-associated idiopathic thrombocytopenic purpura.