Screening for H. pylori infection in children includes invasive and non-invasive tests, the former including rapid urease test, etc. and the latter including carbon 13 urea breath test, etc. 1. Invasive examination: (1) Rapid urease test, gastric mucosa tissue is removed during gastroscopy, rapid urease test is performed, and a positive result suggests the presence of H. pylori infection in the biopsy tissue. (2) histologic examination, take out the gastric mucosa tissue for pathology section, found that there is Helicobacter pylori infection, can confirm the diagnosis, but there may be false negative. 2. Non-invasive examination: (1) carbon 13 urea breath test, carbon 13 has no radioactivity, high sensitivity and specificity, and is currently a commonly used method. (2) fecal Hp antigen test, by doing fecal examination, to determine whether there is Helicobacter pylori infection. (3) Serologic testing for anti-Hp-IgG antibodies, which is not sensitive and prone to false positives. Considering that children have H. pylori infection, the test is generally not recommended, if there are symptoms related to the digestive tract, you need to go to the hospital to let the doctor guide the appropriate test method.