Objective To investigate the value of various post processing techniques of 64 slice spiral CT in the diagnosis of rib fractures. Methods 75 cases of patients with thoracic trauma and suspected rib fractures who were treated in our hospital between February 2014 and February 2016 were selected as study subjects. All of them were examined by X-ray plain film, multi-slice spiral axial CT, volume rendering (VR), multi planar reconstruction (MPR) and other post-processing techniques. The situation of different imaging methods in the detection of rib fractures and number of fractures was compared. Results 165 rib fractures were diagnosed by clinical, imaging examination and reexamination. The detection rates of axial CT and CT post processing techniques in number of cases with rib fractures were 96.00% and 98.67%, respectively. Compared with X-ray plain film (80.00%), the difference was significant (P<0.05). The detection rate of CT post processing techniques in number of rib fractures was 99.39%. Compared with that of X-ray plain film (71.52%) and axial CT (78.79%), there were significant differences (P<0.05). In terms of missed diagnosis, 41 fractures were missed diagnosed by X-ray plain film and the most fractures missed diagnosed located around rib cartilage, accounting for 58.54%. Axial CT missed diagnosed 24 sites, in which 5 sites around the rib cartilage and 5 sites at axillary rib were missed diagnosed; There were no sites missed diagnosed by CT post processing techniques, with 1 suspected fracture. Conclusion The detection rates of 64 slice spiral CT in rib fractures and number of fractures are high, and the rate of missed diagnosis is low, which can effectively make up for X-ray film and axial CT.