Symptoms of diseases caused by H. pylori include bad breath, gastrointestinal symptoms, etc., which need to be analyzed specifically. 1. Bad breath: Helicobacter pylori is one of the direct germs that cause bad breath. There is a large amount of Helicobacter pylori in dental plaque, and the bacterial activity produces metabolites with bad odor, causing bad breath. However, most H. pylori infections are asymptomatic. 2. Gastrointestinal symptoms: 10% to 20%, may develop peptic ulcer, about 10% of patients may develop functional dyspepsia, about less than 1% may cause gastric cancer, and other diseases related to H. pylori infection include gastric mucosa-related lymphoid lymph nodes, gastric polyps and so on. The symptoms mainly include indigestion, acid reflux and heartburn, stomach pain, bloating, anemia, and gastrointestinal bleeding. The symptoms caused by H. pylori infection are many, and it is not possible to identify the specific disease and the extent of the lesion, so it is recommended to consult a doctor in time and follow the doctor’s instructions for symptomatic treatment.