Yellow tongue and bad breath: First, it may be caused by long-term poor oral hygiene environment, to ensure that carefully brush your teeth, rinse your mouth, while brushing your teeth to gently wipe the surface of the tongue to remove the food residue and bacteria on the tongue, to regularly go to the hospital to clean your teeth, through the method of scaling to thoroughly remove the bacteria and tartar on the surface of the teeth and between the teeth, to create a good oral hygiene environment, to make your breath fresh. Make the breath fresh. Second, the tongue is very yellow and thick and has bad breath, may be caused by the body on fire, common in the liver fire and stomach fire people, liver fire people usually have long-term anxiety, tension or irritability, to drink more water and can take the appropriate amount of Xiao Chai Hu Tang, gentian diarrhea liver pill for treatment. People with strong stomach fire are often caused by the accumulation of food that leads to stomach fire rising to the mouth, resulting in a thick yellow tongue and bad breath, so they should eat a light and easy-to-digest diet, not too full at each meal, but mainly seven or eight points full, and do the right amount of exercise after meals, and also take the right amount of drugs to promote digestion, such as the stomach and appetite tablets.