[Objective] To introduce the surgical technique and preliminary clinical outcomes of 3D printed sliding titanium plate for fixation of unstable atlas fracture. [Methods] From April 2018 to April 2021, 9 patients received open reduction and internal fixation with 3D printed personalized sliding titanium plate for unstable atlas fractures. As thin-layer CT scan of the upper cervical vertebra was per- formed before surgery, the 3D model of upper cervical spine was reconstructed using the Mimics software, and then the data captured by the Geomagic Studio software to design the C1 posterior sliding titanium plate, finally the real personalized sliding plate was made by the 3D printer. The posterior cervical incision was made under general anesthesia to expose the posterior arch of C1, establish the vertebral arch screw path. The 3D printed sliding titanium plate was placed to fit the posterior arch, and then insert the screw in proper length. As adjust- ing the plate sliding, the fracture reduction and compressive fixation were finished. [Results] All patients were successfully operated on without serious complications, whereas with operation time of (66.5±7.3)min and intraoperative blood loss of (92.5±27.3)ml, and followed up for 12~18 months. Compared with those preoperatively, the VAS scores [(7.1±1.6), (1.8±1.0), P＜0.05], JOA score [(8.7±6.0), (16.3±4.7), P＜0.05] improved significantly at the latest follow-up. Radiographically, all patients had screw placed properly on images, without screw broken through the bone cortex, while with satisfactory fracture reduction. Up to the last follow-up, all patients got fractures healing without loosening or fracture of the implants. [Conclusion] The 3D printed titanium sliding plate for internal fixation of unstable atlas fracture is feasible, safe and efficient.