Drinking soy milk usually does not cause stomach acidity. When symptoms of stomach acidity occur, the first thing to consider is whether the patient himself has underlying diseases of the digestive system, such as chronic gastritis and gastric ulcer. It is recommended to go to the hospital for gastroscopy to identify stomach diseases, make a diagnosis of gastritis and gastric ulcer, and provide timely treatment. For patients with chronic gastritis and gastric ulcer, indigestion symptoms such as stomach acidity, bloating, nausea and epigastric discomfort are seen. When gastric acid occurs, drugs that inhibit gastric acid secretion can be taken under the guidance of a doctor, commonly used drugs such as omeprazole and pantoprazole are more effective. It can be supplemented with gastric mucosal protective agent treatment, such as Rebapite, bismuth, aluminum hydroxide gel, etc. In addition, if it is caused by Helicobacter pylori infection, systematic eradication treatment of H. pylori should be done. Daily good habits should be developed, quit smoking and limit alcohol, and drink less strong tea and coffee, because these substances can stimulate gastric acid secretion and aggravate the erosion of acid on the digestive tract mucosa.