Abstract:[Objective] To compare the clinical efficacy of arthroscopic versus open Brostr?m-Gould procedure for repair of anterior talofibular ligament (ATFL) in the treatment of chronic lateral ankle instability. [Methods] A retrospective study was conducted on 60 pa- tients who received surgical treatment for chronic lateral ankle instability in our hospitals from August 2018 to September 2019. According to the results of doctor-patient communication, 30 patients underwent arthroscopic repair (the arthroscopic group), while the other 30 pa- tients received open repair (the open group). The perioperative period, follow-up and imaging data were compared between the two groups. [Results] All patients in both groups were operated on successfully without serious complications. The arthroscopic group proved signifi- cantly superior to the open group in terms of total incision length, intraoperative blood loss, intraoperative fluoroscopy times, postoperative walking time and hospital stay (P<0.05). As time went during follow-up period lasted for more than 12 months, the VAS score and eversioninversion range of motion (ROM) significantly declined (P<0.05), while the AOFAS score significantly increased in both groups (P<0.05). At 1 month after operation, the arthroscopic group proved significantly superior to the open group in dorsal extension plantar flexion ROM, eversion-inversion ROM and AOFAS score (P<0.05), whereas which became not statistically significant at 12 months after operation (P> 0.05). In addition, the anterior drawer test and varus test were significantly improved postoperatively in both groups (P<0.05), but there was no significant difference between the two groups at any corresponding time points (P>0.05). Regarding imaging, the anterior displacement and talus tilt under stress on X-ray films significantly decreased in both groups after operation (P<0.05), which were not significantly differ- ent between the two groups at any matching time points (P>0.05). [Conclusion] Both arthroscopic and open Brostr?m-Gould procedures do effectively repair chronic lateral ankle instability. In contrast, the arthroscopic procedure takes a benefit of minimally invasive surgery, which improves functional recovery in short-term.