There are various methods of testing for H. pylori. In the hospital currently commonly used H. pylori detection methods can be roughly divided into two categories of invasive and non-invasive tests. 1, blood test: this method is mainly through the blood test how much H. pylori antibody to determine the H. pylori infection, in general, is not very accurate. Because H. pylori is parasitic on the surface of the gastric mucosa, it usually does not enter the bloodstream, and the antibodies to H. pylori will still exist in the blood for 1 to 2 years after the patient is cured, and a false-positive result will occur during this time. 2, C13 and C14 urea breath test: because C14 is polluting to human body and environment, the isotope will not be declined in human body after taking (all declined period has 60,000 years), so the method is not suitable for pregnant women and children. c13 is not radioactive and will not pollute the environment, the method needs to take the corresponding C13 labeled urea, its sensitivity and specificity is higher. Therefore, the C13 breath test has been recognized as a common and effective method for detecting H. pylori at present. 3, saliva detection method: saliva test plate detection, indirect detection of H. pylori antigen, the determination of urease sensitivity and specificity, the method is targeted, simple and safe and low cost, very suitable for the initial investigation and review of the choice. 4, gastroscopy and gastric mucosal biopsy: its characteristics are histological examination of pathological sections with high accuracy, rapid urease test chemical reaction with low accuracy, because the method belongs to an invasive way, the stomach of H. pylori into a focal distribution, it is possible to take the mucosal parts without bacteria, miss diagnosis, resulting in false negatives, and high cost, so some patients are more rejected, not suitable for census. In conclusion, H. pylori testing consists of two main types of tests, invasive and non-invasive. Blood sampling, C13 and C14 breath tests, and saliva testing are non-invasive tests, while gastroscopy and gastric mucosal biopsy are invasive tests.