Children’s drowsiness may be caused by physiological factors, but also may be craniocerebral disease, vitamin or trace element deficiencies, other diseases and other causes. 1. Physiological factors: children due to prolonged play or excessive fatigue, there will be sleepy symptoms, is a relatively normal physiological response, after rest, the symptoms can be improved. 2. Pathological factors (1) Craniocerebral diseases, such as viral encephalitis, meningitis, acute cerebrovascular lesions, etc., may appear sleepy symptoms, it is recommended to send to the hospital immediately. (2) Some children are deficient in vitamins or other trace elements, such as trace elements of iron, vitamin B, vitamin D and so on, may also have symptoms of drowsiness. (3) Other diseases: idiopathic hypersomnia, sleep-related respiratory disorders and other diseases can also appear sleepy symptoms. There are many reasons for children’s drowsiness, and it is recommended to go to the hospital for timely treatment.