Some children normally do not drool, but when it comes to sleep will drool, this situation is common, mainly due to the following reasons: First, dental malformation. Some children will have malformed teeth due to poor dental development or poor biting habits at a later stage. Especially the front convex teeth, it is easy to lead to sleep when the mouth can not naturally close, resulting in the phenomenon of drooling. Second, oral cleaning is not in place. Some children do not have the habit of brushing their teeth before going to bed, which will lead to the growth of oral bacteria, thus causing oral inflammation, inflammation will cause the phenomenon of increased saliva, thus causing children to drool in bed, accompanied by the phenomenon of teeth grinding. Third, the drug factor. Some drugs will stimulate the mouth to secrete saliva, such as the treatment of muscle convulsions, epilepsy and other diseases drugs. These drugs will stimulate saliva secretion to a certain extent after taking them again, causing the phenomenon of increased salivation. Finally, if the child always sleeps drooling, go to the hospital to do the relevant examination to see if there is a problem with the mouth, if it is a dental problem, but also timely correction, so as to avoid more serious dental deformities when they grow up. In addition, parents should pay attention to supervise the daily hygiene of their children when they take them, and brushing their teeth before going to bed can effectively solve the problem of drooling in bed.