At present, there are many kinds of causes of cranial defects in life, such as traffic accidents, falling objects, debridement decompression, craniosynostosis and so on. Cranial defect not only affects the aesthetics, but also brings insecurity to patients, and even causes problems related to cranial defect syndrome and intracranial pressure instability, which affects patients’ life and work, so it is necessary to repair the skull as early as possible. The ideal cranial bone repair material must have the following conditions: ① easy to shape and fix; ② small tissue reaction, non-toxic; ③ chemically stable, not corroded, absorbed and aged in the tissue; ④ able to pass X-ray; ⑤ no heat transfer, non-conductive. Currently applied cranial bone repair materials mainly include: 1, titanium mesh The more clinically used material is titanium mesh material, but titanium mesh repair cranial rejection is an inevitable problem. Because titanium mesh, a metal material, is more different from human tissue, the histocompatibility is not particularly ideal, so some patients will have rejection reactions. Postoperative problems such as chronic pain, more subcutaneous fluid, sensitivity to hot and cold reactions, and chronic cutting ulcers may occur, and it will also affect postoperative medical examinations such as nuclear magnetic and CT. 2, PEEK material peek material is highly insulated, the patient’s repair will not feel any change in the weather environment; it has excellent mechanical properties, strong impact resistance, and can effectively protect the human brain tissue; from the point of view of cosmetic appearance, peek material is designed according to the patient’s brain CT data, using 3D printing technology to produce a perfect match with the bone window skull; as a non-metallic material, it has stable performance and can be repeatedly autoclaved. Skull repair with peek material is a better choice for many people.