Abstract:[Objective] To introduce the surgical technique and preliminary clinical effect of 3D printed guider assisted open reductionand internal fixation (ORIF) of complex acetabular fractures through a single anterior approach. [Methods] From February 2022 to Septem-ber 2023, 15 patients with complex acetabular fractures were treated by abovementioned surgical procedure. Before surgery, E-3D digitalmedical modeling and design system software was used to reconstruct the pelvis model based on the patient's CT data. After image process-ing, the acetabular fractures were reduced in the pelvis model, and a 1∶1 personalized 3D printed guider for the posterior column screwplacement was designed, made and verified. In the real operation, the acetabular complex fractures were reduced and fixed under assistanceof the guider through a single anterior approach. [Results] All the 15 patients had ORIF performed successfully with the average operationtime of (103.2±11.2) min, with no vascular, nerve injury and other serious complications during the operation. Postoperative radiographsand CT indicated that the anterior and posterior column of fractured acetabulum were well reduced with the posterior column lag screwswell positioned. The follow-up time lasted from 6 months to 12 months, and the fractures were all healed at the last follow-up. The modifiedMerle D' Aubigne and Postel scores were (16.9±1.5), and excellence and good rate of the clinical outcome was of 86.7%. [Conclusion] The3D printed guider assisted ORIF of complex acetabular fractures through a single anterior approach can achieve satisfactory reduction andfixation, and is a safe and reliable surgical technique.