Objective To investigate the clinical diagnostic value of multi-slice spiral CT (MSCT) in thoracolumbar burst fractures. Methods 45 patients with thoracolumbar burst fractures treated in our hospital from March 2013 to June 2015 were taken as the research objects. All the patients underwent X-ray plain film, MSCT plain scan, MPR and VRT postprocessing. The display of number of vertebral fractures and accessory fractures, spinal canal involvement and so on by different detection methods were observed and compared. Results The detection rate of MSCT axial plain scan of the number of vertebral fractures (90%), of accessory fractures (86.8%) and the accuracy of vertebral canal indexing (84.0%) were significantly higher than those of X-ray film (70.0%, 64.8%, 60%) (P<0.05). The differences of MSCT axial position and VRT, MPR and VRT in number of vertebral fractures, the number of accessory fractures, spinal canal involvement were significant(P<0.05). The detection rates of MPR in the number of accessory fractures and spinal canal involvement were significantly higher than those of MSCT axial position (P<0.05). Conclusion Compared with X-ray film, MSCT has more advantages on the segments of vertebral fractures, accessory fractures and spinal canal involvement, especially MPR.