Caries is a common disease in children’s oral cavity, if not treated in time, it is very easy to affect the dental pulp, and cause pulpitis, or periapical inflammation, and affect the growth and development of permanent teeth and milk teeth, and even affect the growth and development of jaw bone, and may also cause the digestive function to decrease, and the nutrition disorder leads to the slow growth and development …… soon after the milk teeth erupt, it can suffer from caries. The calcification degree of the milk teeth of the dentition is bottom, the acid resistance is poor, the teeth and the adjacent surface are easy to retain the bacteria and food debris, and the children’s food is mainly liquid food, semi-liquid food, and sugar food is mostly, it is easy to adhere to the teeth, the sugar in the food, under the action of the bacteria to produce acid, so that the calcified part of the teeth decalcify, and lead to caries. In general, it is difficult for children to maintain oral hygiene consciously, some children eat sweets such as candy and cookies before going to bed, and even sleep with sugar, plus children sleep for a long time, the time of the mouth in a static state is also long, the secretion of saliva is reduced, the role of autogenous sweating is reduced, which provides favorable conditions for bacteria and reproduction, so that the occurrence of caries is greatly increased. How to effectively prevent and control children caries? We should start from the etiology, combine with the developmental characteristics of children and diet, hygiene habits, etc., and make a comprehensive analysis. Specific methods are summarized as follows: 1.Keep oral hygiene: brush teeth every morning and evening, rinse mouth after meals, and master the correct brushing method, it is appropriate to use the smooth brushing method. 2.Fluoride caries prevention: use fluoride toothpaste, or use fluoride drug coating in hospital. 3.Socket closure: For the narrow and deep sockets, using the sockets closure agent can effectively prevent the occurrence of sockets caries. The timing of sealant for milk molar is appropriate for 3-4 years old. 4.Limit the intake of sugar: eat less sugar, avoid eating sugar between meals (the rate of caries is higher if you eat sugar between meals), do not eat sweet food before going to bed, and wash your mouth after eating sugar or sweet food. 5.Dietary caries prevention: eat more fiber food, appropriate amount of protein, vitamin A, D and calcium, phosphorus, etc., can improve the anti-caries ability of teeth and prevent the occurrence of caries. 6.Actively treat the caries that has occurred. 7.Regular examination: Take children to the stomatology department of general hospital for examination regularly. In a word, parents should pay attention to cultivate children’s oral hygiene habit, from the eruption of milk teeth, they should use clean wet gauze to clean their tooth surface. Parents should check and supervise the children’s teeth regularly and treat the caries in time once it is found. The view that the milk teeth will be replaced sooner or later and the caries does not need treatment is wrong.