Objective To explore the efficacy of tumor necrosis factor inhibitor in hip joint lesion of ankylosing spondylids (AS). Methods Eight-six patients with hip joint lesion of ankylosing spondylitis were Enrolled in this study. The treatment protocol was: ①Etanercept 25 mg was suncutaneously injected twice a week in the first two months and once a week in the following two months. Then it was injected once every oth-er two weeks in the last two months of the study period.②Methotrexate 15 mg was administered orally or in-travenously once a week.③NSAIDs and prednisone were stopped when symptoms sunsides. Results Twenty-eight cases (33%) stopped NSAIDs because of the disappearance of symptoms in 2 weeks after starting of the study. Forty-three (50%) stopped NSAIDs with in 8 weeks and 36 cases (42%) in them stopped NSAIDs and prednisone. During the 9th and 16th week, etanercept was used once a week and 49 cases (60%) stopped NSAIDs and prednisone. During the 17th and 24th week, etanercept was used once every two weeks, and 38 cases (44%) stopped NSAIDs and prednisone and their disease was stable. Hip Functional Scores of patients were elevated significantly at 2, 4 and 6 months after the treatment (p<0.05) BASDAI and BASFI decreased, and the difference was significant when compared to those before the treatment (P<0.05). For the 19 cases with hip joint synovitis and hydrarthrosis in MRI image but without obvious change in pelvic plain films, syn-ovitis of 11 cases disappeared and 4 cases improved significantly. In 84 hip joints with grade Ⅱ or Ⅲ changes, 13 joints improved for one grade, 16 joints had improvement but less than one grade, and 49 joints had no radiological changes. Conclusion Etanercept, when combined with methotrexate, is effective in treat-ing hip joint lesion of ankylosing spondylitis. The dosage of etanercept can be tapered after the disease is un-der control.