Mouth taste is generally referred to the symptoms of oral odor, may be due to physiological factors such as improper diet, pathological factors such as dental caries and other related. 1. Physiological factors: eat a stimulating smell of food such as onions, garlic, leeks, etc., may lead to oral odor; oral cleaning is not in place, a large number of bacterial reproduction may also cause oral odor; dimethyl sulfide, quinine and other drugs can also cause a transient oral odor. 2. Pathological factors: oral diseases can cause oral odor, common diseases are caries, periodontitis, oral ulcers, oral cancer, etc.; nasopharyngeal diseases lead to nasal bacterial reproduction, the mouth will also appear odor, common diseases are purulent maxillary sinusitis, tonsillitis, chronic pharyngitis, etc.; dyspepsia, gastritis, diabetes, renal disease, and other diseases can also cause oral odor. There are many factors that lead to mouth odor, it is recommended that patients go to the hospital in a timely manner, under the guidance of the physician to carry out relevant treatment.