Childhood caries is actually more serious and will cause local and systemic effects on children. The local influence should be talked about the masticatory function firstly, if the milk molar, i.e. the milk posterior tooth is decayed and causes the tooth defect, when eating, the masticatory function will be obviously decreased, and it will affect the permanent tooth and the permanent tooth that erupts afterwards, making it more easy to cause caries and decay. Once the caries of milk teeth develops into periapical periodontitis, it will affect the inherited permanent teeth, and the germ of permanent teeth will affect the order and position of eruption, and it will also make the position of permanent teeth abnormal due to insufficient gap when they erupt, and affect the soft tissue of oral mucosa. After the tooth caries occurs, the edge of the broken crown will be sharp, which will stimulate the local tongue, lip and buccal mucosa and affect the soft tissue of oral mucosa greatly. The caries will also cause the systemic effect, once the caries has developed, the caries will further develop and cause the pulpitis and apical inflammation, which will be the foci of the body for a long time, and will cause the low fever, rheumatoid arthritis, arachnoiditis and nephritis in serious cases, and will affect the beauty. When there is serious caries in front teeth area, it will cause serious depression and bad influence to children’s psychology.