The skull is one of the hard tissues in the human body and plays an important role in protecting brain tissue and maintaining a normal and stable intracranial environment. Some people may suffer from cranial defect due to some force majeure, which may endanger their life and health. This requires timely cranial defect repair. Cranial repair is a very ancient surgical procedure that was practiced by our ancestors thousands of years ago, except that the technology was crude and the materials were rudimentary. After thousands of years of development, today, under modern medical conditions, cranial defect repair is a very routine procedure in neurosurgery, and the technique has become more mature. During the development of cranial repair, along with the continuous improvement of surgical techniques, cranial repair materials have also undergone continuous innovation and progress. A very desirable material has now emerged, called polyetheretherketone, or PEEK as it is commonly known. This material is becoming a new trend in cranial repair materials because of its biocompatibility, ability to be complexly shaped, excellent mechanical properties, good protective properties, and high postoperative comfort. Whether in terms of shaping, insulation, strength, or resistance to infection and rejection, PEEK is currently the ideal material for cranial bone repair.