H.pylori is a spiral-shaped, flagellated, gram-negative bacterium that can be found in the gastric mucus layer or attached to the gastric epithelium. It is considered as a major cause of gastritis and peptic ulcer, and it is also closely related to functional dyspepsia, mucosa-associated lymphoid tissue (MALT) lymphoma, and gastric cancer. The World Health Organization’s International Agency for Research on Cancer identified H. pylori as a “group 1 (definite carcinogen)”. H. pylori causes more than 90% of duodenal ulcers and up to 80% of gastric ulcers. Clinically, the detection of H. pylori infection in the gastrointestinal tract can be used as an auxiliary diagnosis for gastritis, gastric ulcer, and gastric cancer.