In recent years, due to the better results obtained by debulking decompression for patients with severe traumatic brain injury, the proportion of the resulting cranial defects has increased. Cranial defects often cause physical and psychological stress to patients, keeping them away from social life. Cranial defect, no matter what the cause is, should be done as soon as the patient’s physical condition allows, not only can improve the quality of life, reduce the patient’s psychological pressure, but also can avoid the discomfort brought by the cranial defect. If patients with skull defect have skull repair, some patients will have dizziness, headache, local tenderness, irritability and restlessness in the long run. Or patients may have fear of pulsation, bulging and collapse of the defect area, fear of sunlight, fear of vibration and even fear of noisy sound, often have poor self-control, concentration and memory loss. If the skull defect is serious, the brain tissue will be injured by the external impact, which can seriously endanger the life and health. At present, we use PEEK material for skull repair, because PEEK material is a new type of skull repair material, many local hospitals do not have this material technology, many patients do not understand this. There are many questions about the use of PEEK for skull repair. The PEEK material is a special engineering material with excellent performance and good histocompatibility, very low rejection, no hot or cold reflection, and the PEEK material is shaped in three dimensions by the cranial CT data, and then the anatomical structure of the skull is perfectly restored through 3D printing technology, which precisely fits the defect area and is currently the better material for cranial repair.