A baby’s white tongue may be due to milk scale, there may also be due to thrush, there may be due to diphtheria. 1. Physiological factors: after the child drinks breast milk or milk powder, if the parents do not help the baby to clean the mouth in time, then it will lead to the tongue and other parts of the milk stains remain, if the local bacterial reproduction, it will form the milk scale, so that the baby appeared the symptoms of the white tongue. 2. Thrush: Thrush is a disease caused by oral candida infection, which can also lead to the symptoms of the baby’s tongue white, in addition to the baby can also appear irritable, refusing to eat and other manifestations. 3. diphtheria: diphtheria is a diphtheria bacillus infection caused by the disease, the disease can also lead to the baby’s tongue white symptoms, in addition, the baby can also appear fever, pharyngeal congestion, “barking” cough and other symptoms. After eliminating the physiological factors, if the symptoms of white tongue persist, it is recommended to consult a doctor to find out the cause of the problem and ask the doctor to deal with it.