Spinal cord injury (SCI) is a severe trauma that leads to significant motor, sensory, and autonomic dysfunction, imposing a substantial disease burden and economic costs globally. The pathophysiology of SCI involves primary and secondary injury stages, with the latter characterized by inflammatory responses, apoptosis, and tissue necrosis. Current therapeutic interventions, including pharmacological treatments and stem cell therapies, provide limited benefits and do not fully address the therapeutic effects on SCI. Hyperbaric oxygen therapy (HBOT), which delivers 100% oxygen at pressures exceeding 1 atmosphere absolute, has shown potential in SCI animal models due to its antiapoptotic, antioxidant, anti-inflammatory, and angiogenesis-promoting effects, thereby limiting secondary injury. Clinical studies have also demonstrated some efficacy of HBOT in treating SCI; however, the optimal timing, duration, and treatment cycles of HBOT remain contentious, and long-term efficacy has yet to be assessed. This review synthesizes the basic research and clinical practice of HBOT for SCI, thereby summarizing the main mechanistic pathways and demonstrating its clinical effects. Future large-scale, multicenter clinical studies are warranted to determine the efficacy and safety of HBOT in treating SCI and explore combined therapeutic modalities for a more comprehensive treatment approach.