Hangman fracture (traumatic spondylolisthesis of the axis) represents a distinct category of upper cervical spine injury in which treatment strategies vary according to fracture morphology, instability, and patient-related factors. While many Levine–Edwards type I fractures can be managed nonoperatively, treatment typically requires rigid external immobilization for at least 4–6 weeks. Prolonged use of a rigid cervical collar is frequently associated with neck pain, reduced cervical mobility, muscle deconditioning, and impaired quality of life, particularly in active or working-age patients. With ongoing advances in endoscopic spinal surgery, minimally invasive posterior fixation techniques have the potential to reduce soft tissue disruption while preserving biomechanical stability. We describe a novel full-endoscopic posterior segmental fixation technique for the management of Hangman fractures and report early clinical and radiographic outcomes. Two patients with Hangman fractures underwent endoscopic posterior C2-only segmental fixation. Under continuous endoscopic visualization, posterior C2 lag screw fixation across the pars fracture was performed through a muscle-sparing approach, aiming to achieve direct fracture compression and segmental stabilization while preserving adjacent segment motion. Operative parameters and perioperative complications were recorded. Clinical outcomes were assessed using the visual analog scale (VAS), Neck Disability Index (NDI), SF-36, and cervical range of motion. Radiographic evaluation included assessment of fracture alignment, implant position, and fracture healing. Endoscopic segmental fixation was successfully completed in both patients without intraoperative complications or neurological deterioration. Intraoperative blood loss was minimal, and no procedure-related adverse events were observed. Postoperative imaging demonstrated satisfactory fracture reduction and stable instrumentation. At 3 months of follow-up, computed tomography confirmed fracture union in both cases. Clinically, both patients experienced marked improvement in neck pain and functional scores and were able to resume daily activities without prolonged external immobilization. These preliminary findings demonstrate that endoscopic posterior C2-only segmental fixation for Hangman fracture is technically feasible and can achieve stable fixation while minimizing posterior soft tissue disruption. This technique may represent a minimally invasive surgical option for carefully selected patients who prioritize enhanced recovery and early return to work.