Milk bubbles on the mouth of newborns may be a normal physiological phenomenon, but also may be caused by disease factors, such as thrush and other diseases. 1. Normal physiological phenomenon: newborn skin mucous membrane is relatively delicate, if the breastfeeding too hard, may be on the lips part of the mucous membrane stimulation, thus appearing similar to the milk bubble-like cover white milk gel-like dots or flakes. 2. Thrush: Thrush is a relatively common disease among infants and young children, usually associated with Candida albicans infection, if the newborn’s immune system is relatively low, it is easy to be infected, resulting in milky mouth bubbles like milky white cover, usually also cry, breastfeeding difficulties, irritability and other symptoms. If there may be other reasons for milk bubbles on the mouth of newborns, it is recommended to go to a regular hospital in time, by the doctor for standardized treatment, so as not to delay the condition.