A foul-smelling gas in the throat may be related to gastroesophageal reflux disease (GERD), tonsillitis, periodontitis and other factors, which should be analyzed reasonably according to the specific situation. 1. Gastroesophageal reflux disease (GERD): If long-term dietary habits are irregular, or overeating, drinking a lot of alcohol, etc., resulting in the food can not be neutralized with gastric acid, so that the food can not be effectively digested, the reflux mechanism between the stomach and the esophagus will be broken, resulting in gastroesophageal reflux, heartburn, acid reflux and other conditions, gastric acid stimulation of the throat will make the throat with a foul odor appear. 2. tonsillitis: tonsillitis is generally caused by pathogenic microbial infections caused by the disease, the patient can be manifested as loss of appetite, sore throat, cough and other symptoms, but also make the tonsil crypts appear pus embolus or cheese-like secretion, which will stimulate the gastrointestinal tract, in the role of the bacteria will make the throat appear foul-smelling. 3. periodontitis: the throat odor may be associated with oral bacterial growth, such as periodontitis, a chronic inflammation of the periodontal tissues, which can lead to red and swollen gums, periodontal pockets overflowing with pus and teeth loosening and other conditions, severe cases can be accompanied by the throat and mouth odor. Therefore, when there is a foul odor in the throat, it is necessary to go to the hospital in a timely manner to check, clarify the specific causes and active treatment, to avoid affecting the normal life.