Smelly mouth in children may be related to bad habits, indigestion, gum inflammation and other reasons. 1. Bad habits: if children eat greasy, irritating flavor of food, and do not pay attention to oral hygiene, there may be bad breath, it is recommended to develop a good habit of brushing teeth to ensure oral hygiene. 2. Indigestion: If children have indigestion, they may have bad breath and bloating, which can be treated with bifidobacteria and other medicines under the guidance of doctors, and it is recommended that they eat more easy-to-digest food and don’t overeat. 3. Inflammation of the gums: If the child’s gums are inflamed, it may also cause bad breath, gum pain, swelling, etc., can be recommended by the doctor to remove tartar and plaque control and other treatments. Children with bad breath that cannot be relieved should go to the hospital for diagnosis and treatment. All of the above medications should be used under a doctor’s supervision.