Thoracolumbar junction (TLJ) injury is one of the most common spine injuries. TLJ injury manifesting as neurologic deficit usually requires surgery because of the underlying spinal instability and/or neural compression. The objectives of surgical treatment are to restore biomechanical stability of the spine and/or to achieve neural decompression. The short-term outcomes were evaluated of 32 patients with symptomatic TLJ (T11-L2) injury who underwent posterior instrumentation surgery in the acute stage between 2000 and 2004. Seventeen patients had unstable burst fracture and 15 patients had either flexion-distraction or fracture-dislocation injury of the TLJ. Fifteen patients had American Spinal Injury Association (ASIA) classification Grade-A, eight had Grade-B, seven had Grade-C, and two had Grade-D preoperative neurologic deficits. All patients underwent posterior instrumentation surgery using pedicle screws and connecting rods, fixed to two vertebral levels above and below the injured segment. No patient experienced neurologic deterioration perioperatively. Postoperative recovery evaluated 3 months after discharge heavily depended on the preoperative neurologic status: patients with ASIA Grade-A deficits usually had limited neurologic recovery, whereas some with Grade-C or D became ambulatory. Complications occurred in five patients, but none suffered death or permanent morbidity. Posterior instrumentation surgery is a safe and efficacious treatment for patients with symptomatic TLJ injury. Long-term efficacy of the posterior instrumentation surgery is less clear, because of the limited duration of the follow-up period.