Spinal cord injury is a serious disabling condition. Transplantation of olfactory ensheathing cells (OECs) is one of the most promising treatments for spinal cord injury (SCI). Thirty-nine patients with chronic SCI received OEC transplantation and completed long-term follow-up, with a minimum follow-up of 7 years. We assessed sensorimotor function with the American Spinal Injury Association (ASIA) Impairment Scale (AIS) and autonomic nervous function by the International Standards to document remaining Autonomic Function after Spinal Cord Injury (ISAFSCI), and sympathetic skin responses (SSR). The scores of each group were significantly higher after OECs transplantation than before treatment. SSR latencies were shorter and response amplitudes increased after treatment. Long-term follow-up showed further improvement only in motor function and autonomic function compared with 3 months postoperatively. No complications occurred in any patient during long-term follow-up. The results indicate that the transplantation of OECs in spinal cord restored function without serious side effects.