How long it takes to rule out brain hemorrhage after a head impact depends largely on the severity of the patient’s injury and cannot be generalized. A patient with a head impact may usually result in an intracranial hematoma, intracranial hemorrhage, etc. In the case of acute intracranial hemorrhage, a delayed hematoma will form within 24 hours. In the case of subacute intracranial hemorrhage, the risk period for bleeding is within 72 hours after the head is hit. Some patients may also develop intracranial hemorrhage beyond 72 hours, mostly in the elderly. Slow onset secondary epidural or subdural hematomas may occur in the elderly because of their vascular configuration, physical reasons, and other factors that require attention. Clinically, brain hemorrhage can be basically ruled out for those who have no symptoms present for more than 3 months after head impact, or for those who have no bleeding on multiple cranial CT examinations within 72 hours. Patients with head bruises need to go to the neurosurgery department of regular hospitals for timely examination, and cranial CT examinations can be routinely performed to exclude intracranial hemorrhage and cranial contusions.