The white stuff in the newborn’s mouth may be caused by physiological factors, such as milk residue, and may also be caused by pathological factors, such as thrush. 1. Physiological factors: Parents do not strengthen the oral care of newborns, and do not clean up the milk residue in time after breastfeeding, leading to the emergence of the above conditions. 2. Pathological factors: Thrush is common, caused by Candida infection of the oral mucosa, the symptoms are mainly scattered white spots in the mouth, slightly higher than the oral mucosa, may also be accompanied by refusal to eat, crying and other symptoms. Once diagnosed, symptomatic treatment should be given in a timely manner to avoid the aggravation of the disease spreading to the tonsils and pharynx, etc. Parents are advised to strengthen the care of newborns. Parents are advised to strengthen the care of newborns, pay more attention to observation, find abnormalities and timely consultation, and give symptomatic treatment as soon as possible.