Analyzing and comparing of x-ray imaging and computed tomography features in diagnosis of C2 fracture. Methods: Cross-sectional descripted retrospective studying of 64 C2 fracture patients were diagnosed in Viet Duc hospital from January 2010 to June 2012. Results: 44 patients had odontoid fracture, 14 patients had Hangman’s fracture, 6 patients had C2 vertebral body fracture. Open-mouth X-ray view was diagnosed 81,8% cases of odontoid fracture, lateral view was diagnosed 68,2% cases of Hangman’s fracture, anteroposterior views couldn’t find C2 fracture. On computed tomography imaging, type 2 of odontoid fracture rates was 86,4%, type 3 of Hangman’s fracture rates was 78,7%, type 3 of vertebral body C2 fracture was rates 50%. The Kappa value (0,44) for measuring the reliability between X-ray and CT in findings of C2 fractures was moderate. Conclusion: X-ray plays an important role in screening and emergency diagnosis of C2 fracture. The reliability between X-ray and CT in findings of C2 fractures was moderate. Computed tomography imaging was gold standard for diagnose and classify C2 fracture.