The bottle is a tool for manual feeding of the breastfed child. During the weaning period, the bottle is gradually used instead of milk by other drinks. Some babies will sleep with the bottle in their mouths, but using the bottle wrongly for a long time is the reason for the occurrence of dental caries, especially using the bottle while sleeping, so that the milk or drink stays in the mouth and induces dental caries. The serious caries of maxillary front teeth (incisors) and maxillary first milk molar is called bottle caries. The baby’s milk teeth start to erupt in the mouth around 6 months after birth. Parents do not want their children’s teeth to get caries. However, many parents don’t know what to do to avoid or reduce caries, and in 1987, the survey report of Japanese Ministry of Health and Welfare on children’s dental disease pointed out that: the caries rate of children increases rapidly from 2 to 3 years old, and reaches 90% or more around 6 years old, and almost all children suffer from caries. This pattern also exists in the survey of children’s caries in other countries. How to use milk bottle correctly? It is necessary to know that the most likely cause of dental caries is to use the bottle while sleeping. The worst habit is that the baby sleeps with the bottle in his mouth. Therefore, the use of bottle should be stopped after 1 year old. Long-term use not only induces tooth decay, but also prolongs the time of leaving breast milk and affects the development of the baby’s mental independence. In addition, we must pay attention to the contents of the bottle, such as feeding orange juice, lactic acid drink or adding a lot of sugar to the milk, which will not only induce caries but also affect the taste of the baby in the future.