How long a child will vomit after a head fall can not be directly determined, some children may vomit within 24 hours after a head fall, serious cases immediately after the fall or within a short period of time, but there are also some children will not vomit. There is no strict standard for the time of vomiting after a child’s head fall, if the child’s situation after the fall is relatively mild, there is no immediate abnormal vomiting, loss of consciousness and other abnormal manifestations, just pain, shock, short crying, after which the child can soon be normal eating, playing, sleeping, etc., can be dynamically observed for 48-72 hours. If the situation is more serious, there may be vomiting, and accompanied by bleeding, depression, or even sleepiness, convulsions and other problems, we must promptly seek medical attention. Generally children need to be taken to the hospital for head CT examination in a timely manner after a head fall to determine whether there is any craniocerebral injury, and if the situation is more serious, surgical treatment may be required to avoid a more dangerous situation.