In my clinical work, I often meet parents who bring their children to consult about “drooling”. In fact, what we call “saliva” is medically known as saliva, which is secreted by three pairs of salivary glands in the mouth. Saliva contains many kinds of digestive enzymes, which play a great role in helping to digest food. In the newborn period, the salivary glands are not fully developed, so the amount of saliva is small. At the beginning of 5-6 months, the glands begin to develop, and at the same time, with the increase of complementary food, the growth of milk teeth, more prompted the increase of saliva secretion, but the volume of the mouth is relatively small, swallowing regulation function is poor, often too late to swallow and out of the mouth, and with the growth of age this phenomenon also gradually disappeared. But every time new teeth grow, due to the stimulation of salivary glands, the secretion also increases and leads to saliva outflow. These are normal “drooling” phenomena. However, some diseases can also cause drooling. Such as common stomatitis, tongue inflammation, pharyngitis, tonsillitis, can appear temporary drooling, but after healing, no longer drooling. If the persistent drooling is mostly seen in brain disorders. Such as encephalitis, meningitis sequelae and congenital brain dysplasia. Because these diseases make the brain have substantial functional lesions, so the swallowing function of regulating saliva is poor. Due to long-term or short-term drooling, the corners of the mouth on both sides are eroded. The skin of the lower jaw is often impregnated with saliva, resulting in redness of the skin, eczema or epidermal rupture and ulceration, and secondary bacterial infection, so it is important to keep the local skin dry. If necessary, bring a “scarf” or “saliva cloth”. If there is oral disease caused by drooling, it should be actively treated. Make sure to pay attention to oral and hand hygiene, brush your teeth and wash your hands frequently. Brain disorders should be treated by a specialist.