Cranial depression may be caused by craniocerebral injury, or it may be caused by medical reasons, a small number of them can recover by themselves, most of them need surgical repair. 1. Craniocerebral injury: If the skull is hit by external force resulting in craniocerebral injury, it will cause cranial depression. Generally speaking, children with mild cranial depression do not need treatment and can recover on their own with growth and development. If the skull depression occurs in adults, the degree of depression is more than 5 millimeters, and the function of the brain tissue is abnormal, it is generally difficult to repair by itself, and should be repaired through surgery as soon as possible. 2. Medical causes: In the process of cranial surgery, because the skull is not fixed properly, it will also be sunken inward. In this case, it is also difficult to repair the depression of the skull by itself, and a second surgery is needed to repair and fix it. It is recommended that patients with cranial depression should consult a doctor in time, and choose the appropriate treatment with the examination and the analysis of the professional doctor’s opinion.