The main diseases that cause red and swollen gums in children are gingivitis, periapical inflammation of the milk teeth, gum ulcers, herpes stomatitis, and Candida stomatitis. If the gums of young infants and children whose milk teeth have not yet erupted are red and swollen, it is mostly due to herpes stomatitis or candida stomatitis. Herpes stomatitis requires antiviral treatment, and the child can be given oral pellets of Banlangen, drink more water, and get enough rest and sleep; candida stomatitis can be treated with gauze dipped in baking soda solution and gently wiped on the mucous membrane of the child’s mouth, and bottles and nipples can be disinfected and cleaned. Children whose milk teeth have erupted can also have red and swollen gums caused by dental and gum disease, and gingivitis caused by unclean brushing, when parents should assist the child to clean the tooth surface and take the child to the hospital for scaling if necessary. Periapical inflammation of milk teeth is also the main cause of localized redness and swelling of the gums, which can be treated with oral erythromycin and root canal treatment at the hospital. Children with gum mucosal ulcers can be sprayed locally with watermelon cream spray or open throat sword spray.