Temporomandibular joint osteoarthritis (TMJOA) is the most common degenerative disease in the temporomandibular joint, mainly manifesting with pain in the joints and the muscles, joint locking, popping, crepitus, and limited mouth opening, which may undermine the quality of patients' life. The main pathological features of TMJOA include chronic synovitis, progressive articular cartilage degeneration, and abnormal subchondral bone remodeling. At present, its pathogenesis is still unclear, and abnormal mechanical load, trauma, heredity, metabolism, gender and age can all be regarded as pathogenic factors. Commonly used diagnostic methods for TMJOA include magnetic resonance imaging (MRI) and computed tomography [(CT/cone beam CT (CBCT)]. The staging standards of TMJOA mainly include Wilkes staging system and Yang's staging system. The clinical treatment of TMJOA mainly includes two categories: non-surgical treatment and surgical treatment. Non-surgical treatment includes health education, psychological consultation, medication, occlusion treatment, etc. Surgical treatment includes arthrocentesis, arthroscopic surgery, disc anchoring, autogenous tissue graft, and total joint replacement. This paper summarizes the diagnosis, staging, surgical treatment and postoperative evaluation of TMJOA on the basis of literature review, and proposes diagnosis and treatment protocols based on the experience of the TMJ Center of Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, so as to provide reference for clinicians.