Objective To study the operative procedure and the effectiveness of arthroscopic therapy for ankle joint impingement syndrome after operation of ankle joint fracture dislocation. Methods Between March 2008 and April 2010, 38 patients with ankle joint impingement syndrome after operation of ankle joint fracture dislocation were treated. Among them, therewere 28 males and 10 females with an average age of 28 years (range, 18 to 42 years). The time from internal fixation to admission was 12-16 months (mean, 13.8 months). There were pressing pain in anterolateral and anterior ankle. The dorsal extension ranged from — 20 to — 5° (mean, —10.6°), and the palmar flexion was 30-40° (mean, 35.5°). The total score was 48.32 ± 9.24 and the pain score was 7.26 ± 1.22 before operation according to American Orthopaedic Foot and Ankle Society (AOFAS) ankle and hindfoot score system. The X-ray films showed osteophyte formation in anterior tibia and talus; MRI showed cartilage injury in 22 cases. Arthroscopic intervention included removing osteophytes, debriding fabric scars and synovial membrane tissues, and removing osteochondral fragments. Arthroscopic microfracture technique was used in 22 patients with cartilage injury. Results All incisions healed primarily. Thirty-eight cases were followed up 10-26 months (mean, 16 months). At last follow-up, 26 patients had normal range of motion (ROM); the dorsal extension was 15-25° (mean, 19.6°) and the palmar flexion was 35-45° (mean, 40.7°). Eight patients had mild l imited ROM; the dorsal extension was 5-15° (mean, 7.2°) and the palmar flexion was 35-45° (mean, 39.5°). Four patients had mild l imited ROM and pain in posterior portion of the ankle after a long walking (3-4 hours); the dorsal extension was 0-5° (mean, 2.6°) and the palmar flexion was 35-40° (mean, 37.5°). The total score was 89.45 ± 9.55 and the pain score was 1.42 ± 1.26 after operation according to AOFAS ankle and hindfoot score system, showing significant differences when compared with preoperative ones (t=21.962, P=0.000; t=16.762, P=0.000). Conclusion Arthroscopic treatment of ankle joint impingement syndrome after operation of ankle joint fracture dislocation is an effective, simple, and safe method.