When eating with a bitter mouth, we must first clarify whether it is before eating, after eating, or there is something wrong with what we eat. In addition, we must determine whether the bitterness of the patient’s eating mouth belongs to something that happens in the short term, or something that lasts for a long time. If it happens in the short term, observe whether there are abnormal changes in the short term, whether there are other comorbidities, whether there are abnormal living habits and eating habits of patients, such as excessive smoking, drinking, binge drinking, overeating, staying up late, etc., and whether there are abnormal infections in the mouth in the near future, such as pharyngitis, gingivitis, mumps, tonsillitis, etc., all these factors may cause the bitter eating mouth situation. In addition, if the patient has bitter mouth after eating and lasts for a long time, he should pay attention to whether it is related to gastrointestinal digestive malfunction or liver and gallbladder related diseases, such as liver and gallbladder stones, biliary tract infection, abnormal liver function, gastric ulcer, gastritis, etc. Especially the pylorus and cardia of the stomach are relaxed, which easily leads to bile reflux and thus the symptoms of bitter mouth.