Bitter mouth is more causes, it may be physiological, but also may be related to some pathological factors, such as pathology is common in some oral diseases, gastrointestinal diseases and other causes. 1. Physiological reasons are common in drinking less water, lack of sleep and other reasons, this situation is easy to make the human body’s nerve function disorders, which is easy to appear dry mouth, bitter mouth phenomenon. Also do not pay attention to oral hygiene, or usually like to eat some bitter food, such as bitter melon, etc., are prone to bitter mouth. 2. Pathological factors leading to the symptoms of bitter mouth, and some oral diseases, such as gingivitis, periodontitis, dental caries, etc., due to dental caries caused by food residues, corruption of bacteria, as well as some inflammatory diseases in the oral cavity, inflammatory secretions, which will make the oral cavity with a peculiar taste and symptoms such as bitter mouth. 3. Some stomach diseases, such as reflux esophagitis, chronic gastritis, etc., due to bile reflux, gastrointestinal dynamics is poor, gastric acid and other reasons for the patient’s mouth, also can make the patient’s mouth appear bitter. In addition, there are other causes of pathologic bitter mouth, it is recommended that the patient should consult a doctor in time to determine whether there are pathological factors, and can give timely targeted treatment.