Bitter mouth from eating is a symptom of many diseases. Oral diseases, gastrointestinal diseases, liver and gallbladder diseases are mostly considered. 1. Oral diseases: such as dental caries, periodontitis, oral ulcers and other oral diseases, due to the patient does not pay attention to oral hygiene, there may be symptoms of bitter mouth. 2. Gastrointestinal diseases: various reasons lead to digestive tract dysfunction, the patient’s gastrointestinal peristalsis slows down, bile reflux to the stomach after eating, leading to symptoms such as bitter mouth after eating. 3. Liver and gallbladder diseases: such as gallbladder stones, acute cholecystitis, cholangitis and other diseases, leading to the decline of gallbladder function or bile discharge is not smooth, causing bile reflux, the symptoms of bitter mouth. It is recommended that patients with symptoms of discomfort should consult a doctor in a timely manner, under the guidance of the doctor to choose the appropriate treatment program, to avoid delaying the condition of self-medication.