When mouth ulcers appear in the baby’s mouth, it is important to identify the cause of the mouth ulcers. Generally mouth ulcers are divided into recurrent ulcers and traumatic ulcers. If it is a recurrent ulcer, it is important to check what is causing the ulcer to recur. If it is a traumatic ulcer, the local irritant needs to be removed. Generally, mouth ulcers do not need to take any medicine, but can be used topically. For the baby’s mouth ulcer, usually keep the mouth clean, the baby’s diet should be supplemented with nutrition, eat more vitamin-rich food, not to eat stimulating food. If there is a traumatic ulcer caused by tooth decay, treat the tooth decay in time. Parents must pay attention to the health problems of teeth in the mouth, take the baby to check the teeth regularly, and do the filling treatment in time if there is tooth decay. For children’s mouth ulcers, you can use watermelon cream spray or children’s version of open throat sword spray topically, and prevent local infection, develop good habits of brushing teeth, and maintain good oral hygiene. You should eat a reasonable diet, eat more fruits and vegetables, do not be picky about what you eat, and replenish some of the trace elements that are missing in your baby’s body, so as to benefit the oral health of children.