It is recommended to observe the baby for 1-3 days after knocking the back of the head, including mental, dietary, behavioral and other manifestations, the specific observation time varies according to individual circumstances. If the baby is hit on the back of the head, there is no obvious trauma, and there is no significant abnormality in spirit, diet and behavior, the baby can be observed at home for 1-3 days; if there is visible head trauma, such as redness, swelling, bleeding, cracks, etc., the baby should be treated in time to prevent infections; if there is vomiting, pain, coma, convulsions, fever, crying, etc., the baby needs to be considered to be in an emergency situation, such as a fracture of the skull or intracranial hemorrhage. It is recommended to go to the hospital immediately for head CT or MRI and other auxiliary examinations to clarify the diagnosis and give corresponding treatment measures as soon as possible. After a baby hits the back of the head, it is recommended to go to the hospital to complete the relevant examinations to understand the injury, and if no abnormality is found, it is recommended to observe the baby for at least 72 hours. Parents should enhance the care measures to reduce the risk of cranial injury in babies.