A child who falls and has a large bag on the back of the head is usually a subcutaneous hematoma. First of all, we should observe the injury site, and also observe the child’s consciousness and activity, and then take appropriate measures according to the specific situation, once the abnormal situation is recommended to send to the doctor. Observe 1. Observe the injury site: observe whether there is any breakage or bleeding after the incident; 2. Observe the child’s consciousness: observe whether the child cries out immediately and whether there is any change in consciousness. Some children may experience sudden drowsiness or loss of consciousness after a fall; 3. Observe the child’s activity: observe whether there is any abnormality in the child’s limb movement, whether there is motor impairment or sensory impairment, and also observe whether the child is accompanied by headache, nausea, vomiting and other symptoms. Treatment 1, there are abnormalities: If the child falls and starts to bag, there is a wound rupture and bleeding, accompanied by impaired consciousness, limited limb movement, vomiting, severe headache and other manifestations, it should be immediately sent to the hospital to confirm the diagnosis using CT, by professional physicians according to the specific situation. If it is determined that there is no intracranial injury, observe the child for at least 72 hours. If the child has no obvious clinical symptoms within 72 hours, it means that this trauma has no obvious effect on the child; 2. No abnormalities: If the child has a bag after the fall, but there is no bleeding, impaired consciousness, limited limb movement, vomiting, headache and other abnormal manifestations, cold compresses can be applied intermittently for 48 hours, and if it does not subside after 48 hours, local hot compresses can be applied to promote the local swelling to subside. Before the swelling subsides, take care not to squeeze or touch the large bag in daily life or when sleeping to prevent secondary injury. If the big bag is more painful, you can use a pain relief spray.