Abstract: Aiming at the actual clinical navigation needs of minimally invasive spine surgery, an augmented reality-based navigation system for minimally invasive spinal surgery is designed and developed. The scan and reconstruction of the patient's spine lesions are realized by CT (computed tomography) before surgery, and the appropriate spine model is imported into the Unity-3D platform to add control scripts for it. To achieve the synchronous display of medical images of surgical instrument and lesion model, the calibration ball is adopted to calibrate surgical instruments, the Polaris Vega optical tracker is used to track surgical instruments in real time, the coordinate conversion relationship between surgical instrument and Polaris Vega optical tracker is established, and the posture information of the identified surgical instrument is sent to HoloLens device in real time. During surgery, it provides doctors with three-dimensional images to visualize spinal lesions, helping doctors to locate lesions and navigate surgical instruments. The experimental test on the spine model show that the system navigation error is less than 2.8 mm, which can meet the requirements of clinical application in spine surgery.