Drooling in children may be related to physiological factors, but also may be the emergence of mouth ulcers, colds and other diseases. 1. Physiological factors, children’s dental development is not mature enough, alveolar shallow, swallowing function is not perfect, excessive secretion of saliva can not be swallowed quickly, so there may be children drooling. 2. Mouth ulcers, clinically, mouth ulcers stimulate the salivary glands after inflammation, resulting in excessive salivary secretion, appearing children drooling. 3. Colds, some children with colds bacteria or other pathogens invasion, salivary gland secretion is abnormal, so may appear children drooling situation. Children drooling may also have other reasons, it is recommended to go to the hospital in a timely manner, improve the examination to clarify the cause of the disease, give targeted treatment or treatment.