Cranial defects are often associated with headache, local tenderness, irritability, restlessness, etc.; or fear of local collapse and pulsation. As a large skull defect causes serious deformation of the patient’s head, it directly affects the physiological balance of intracranial pressure, and because the atmospheric pressure acts directly on the brain tissue through the defect area, it will inevitably lead to local brain atrophy and aggravate the symptoms of brain wasting after a certain period of time. Therefore, patients with cranial damage should receive timely repair surgery. Cranial repair surgery is not a very difficult procedure in the field of neurosurgery, and the risk factor is not very high. However, the appropriateness of this type of surgery and when to perform cranial repair should be determined on a patient-by-patient basis. For patients with open skull comminuted fractures with clean wounds and no cranial hypertension, it is recommended to perform cranioplasty in one week; while for patients with severe closed craniocerebral trauma, the better time is about three months for giant cranial defects caused by decompression of large bone flaps performed for cranial hypertension. In addition to the timing of cranial repair surgery, the choice of material is also crucial. Good materials not only provide better repair results, but also reduce the chance of complications. Currently, we use the latest PEEK bionic material, which has superior mechanical and thermal properties, and is highly biocompatible and can perfectly realize the symbiosis of cranial bone, which is a safe and effective material for cranial bone repair.