The unpleasant odor from the stomach is usually caused by incomplete digestion and absorption of food in the stomach, usually due to gastric insufficiency, chronic gastric disease, H. pylori infection and pyloric obstruction. Patients are advised to visit the clinic for relevant examinations to choose the treatment for the cause. Common causes and treatment: 1, gastric power deficiency: that is, indigestion, usually due to mood swings, gastric secretion dysfunction and other factors, can lead to epigastric distension, bloating after meals and other indigestion symptoms, food accumulation and fermentation, thus causing odor. Patients can follow medical advice to use pro-gastric power drugs to accelerate gastrointestinal peristalsis; 2, stomach diseases: common in chronic gastritis, gastroesophageal reflux and other diseases, gastroscopy is needed to clarify the diagnosis, and then symptomatic treatment. Usually, omeprazole and ranitidine can be applied under the guidance of professional doctors to inhibit gastric acid secretion, and gastric mucosal protectors such as bismuth potassium citrate and colloidal bismuth pectin can be used to relieve symptoms. In daily life also need to pay attention to a light diet, appropriate exercise to strengthen physical fitness, resistance to disease; 3, H. pylori infection: urease secreted by H. pylori can break down carbon dioxide and ammonia, through the esophagus and oral discharge, thus producing odor. Generally, H. pylori eradication treatment can be performed under the guidance of a professional doctor, often applying quadruple therapy, such as omeprazole, amoxicillin, clarithromycin, colloidal bismuth pectin combination of drugs. In daily life, pay attention to dietary hygiene, avoid sharing utensils with others or long-term close contact with infected people; 4. Pyloric obstruction: it can be caused by food or gastric juice not passing through the pylorus normally, resulting in acid reflux, abdominal pain, belching and other symptoms. Drugs such as rabeprazole can be used as prescribed by the doctor to inhibit gastric acid secretion and relieve symptoms. Daily attention should be paid to a healthy diet, avoiding alcohol, strong tea, coffee and other stimulating beverages to avoid causing ulcers leading to the appearance of symptoms.