Abstract: A three-month-old Poodle accidentally fell from a height about one week before the treatment, and then continued to suffer from neck pain and restricted mobility.In order to diagnose and treat this case, the trial used clinical examination, imaging examination and laboratory examination to confirm the diagnosis, and the treatment was carried out based on diagnosis results. The results showed that the dog had atlantoaxial dislocation accompanied by central nerve compression. The prognosis of the dog was good after atlantoaxial joint fixation by surgical methods. The results suggested that atlantoaxial arthrodesis was the most effective method to treat this type of disease.