Bitter mouth and bad breath in the morning is related to diet, and may also be related to oral diseases and digestive disorders. Eating spicy and stimulating foods the day before, or heavy foods such as stinky tofu, chili peppers, or garlic can cause bitter mouth and bad breath when you wake up the next morning. It can be relieved by brushing your teeth or changing your diet. Poor oral hygiene, tartar or plaque around the teeth, or untreated dental caries can also cause bitter breath and bad breath, and require scaling and dental treatment to improve, while paying attention to maintaining oral hygiene. If the digestive system function problems, indigestion will also appear bitter mouth bad breath phenomenon. Therefore, early morning bitter mouth with bad breath is mostly seen in the above situation, if long-term bitter mouth and bad breath can not be relieved need to go to the stomatology department for medical treatment.