This retrospective study aimed to evaluate midterm outcomes of surgical management of multi-segment thoracic spinal tuberculosis by single-stage posterior transforaminal debridement and interbody fusion with instrumentation. From January 2007 to October 2015, 42 adult patients with thoracic spinal tuberculosis involving three or more levels underwent single-stage posterior transforaminal debridement, interbody fusion and instrumentation At a mean follow-up of 73.5 ± 9.6 months, all patients were eligible for final evaluation. All displayed improved biochemical markers and pain scores at 3 months and improved physiologic levels at the end of treatment. Visual analogue and 36-Item Short-Form Health Survey scores were significantly improved compared with preoperative values. All 30 patients with preoperative neurological deficits experienced neurologic improvement. Thoracic kyphosis angle decreased significantly from 34.4° ± 4.5° to 22.0° ± 2.6°. A mean kyphotic angle loss of 1.7° ± 1.1° was recorded at the final follow-up, and bone fusion was observed at a mean of 10.6 ± 2.1 months, with no instrumentation failures. One patient experienced delayed incisional healing and five patients suffered postoperative intercostal neuralgia that were cured by conservative treatment. There were no graft failures or implant breakages. This study showed the utility of a single-staged procedure combining posterior transforaminal debridement and interbody fusion with instrumentation, and demonstrated promising results.