To evaluate the utility and clinical experience of using three-dimensional (3D) topographic bone thickness map in skull lesion resection and one-stage cranioplasty.;A retrospective analysis was conducted on 32 patients who underwent skull lesion resection and one-stage cranioplasty using poly-ether-ether-ketone (PEEK) between December 2019 and December 2023. Preoperative thin-slice cranial CT data were used to reconstruct 3D topographic bone thickness maps employing a pseudo-color technique to determine lesion margins, fabricate PEEK implant and make surgical strategies (topographic group). The conventional group used similar workflow with the conventional 3D CT images. Cranioplasty was carried out with PEEK implants following lesion resection at the same time.;Patients' ages ranged from 3 years to 67 years (median: 26 years). Postoperative pathology confirmed Langerhans cell histiocytosis (LCH, n=8), fibrous dysplasia (n=8), meningioma (n=13), lymphoma (n=2), sarcoma (n=1). Partial resection was performed in four fibrous dysplasia and three LCH cases, while the remaining 25 cases underwent total resection. No severe complications such as hemorrhage, infection, or poor wound healing were observed. Three patients with multi-site LCH received postoperative chemotherapy and three patients with aggressive meningiomas underwent radiotherapy after surgery. Follow-up over 2-6 years revealed no recurrence. In the topographic group, the PEEK implants achieved universally accurate intraoperative fit, and the operative time was significantly shorter than that of the conventional group.;The 3D topographic bone thickness map holds clinical value (precise, convenient and time-saving) in guiding skull lesion resection and cranioplasty.;