Objective To investigate the clinical effect of pedicle screw fixation in the treatment of fracture and dislocation of atlantoaxial spine via posterior approach .Methods 19 patients with fracture and dislocation of atlantoaxial spine in this hospital from June 2011 to December 2013 were selected and treated with open reduction and pedicle screw fixation via posterior approach . The X‐radiographs were postoperatively re‐examined at regular time for understanding the correction of fracture and dislocation and implant fusion results ,the neurological functions were evaluated according to the Japanese Orthopaedic Association(JOA) scores . Results All cases got bony fusion without the occurrence of internal fixation loosening ,broken screw or broken rod .The JOA score was improved from preoperative (7 .35 ± 2 .39) points to postoperative (13 .21 ± 2 .53) points (P<0 .05) .Conclusion The posteri‐or atlantoaxial pedicle screw fixation and fusion for treating upper cervical spine injury has satisfactory effect .