Due to the characteristics of the age of the baby, oral cleaning is not done properly, the maintenance of oral hygiene is more difficult, in addition, many babies grow up drinking milk powder and sugary diet control is not in place, often appear yellowing of the teeth. The real reason of yellowing teeth needs to be diagnosed by professional dentist in hospital, and then find out the reason and deal with the cause and protection. The yellowing of teeth is usually caused by caries in the first stage, and gradually it will become black and decayed. If yellowing is caused by caries, parents should help baby to do preventive work, as long as there is no caries, baby will be fine after getting new teeth. For preschool children, it is generally recommended to have oral examination every 3 months, and for school-age children, every 6 months; control foods and drinks with high sugar content in diet, avoid foods with strong adhesion and long stay in the mouth, clean the mouth after eating, do not eat snacks and drinks before and after meals, and use milk bottles reasonably; parents should guide the baby to establish good brushing habits. Some baby teeth that are yellowed due to tartar or calculus and parents mind it very much, then you can do scaling treatment and also need to have good oral cleaning habits. There is another situation, related to the quality of drinking water, due to which the fluoride content is too high will cause dental fluorosis, the symptoms will also be yellowing on the teeth, generally the upper front teeth are more obvious. If this is the cause of yellow teeth, then consider changing the source of drinking water. Regardless of the cause of yellowing baby teeth, at this stage, parents should establish systematic knowledge of baby oral hygiene and guide baby to correct some bad habits, and cooperate in the prevention and treatment of baby oral diseases under the guidance of dentists.