Abstract Objective To investigate the clinical outcomes of arthroscopic debridement combined with anatomical reconstruction of the lateral collateral ligament for treatment of chronic lateral ankle instability. Methods From October 2016 to October 2018, 18 consecutive patients with CLAI were retrospectively studied. Ankle arthroscopic debridement was performed, and then the ipsilateral peroneus brevis tendon was used to reconstruct anterior talofibular ligament and calcaneofibular ligament. AOFAS and VAS)were used to evaluate the recovery of ankle function at preoperation and postoperative final follow-up. Results All the 18 cases were successfully operated without serious complications. Postoperative X-ray showed that the position of the ankle joint was normal, MRI showed that ATFL and CFL had normal shape and good tension. The average follow-up time was （19.89±1.68） months. According to the AOFAS score, the postoperative effect was excellent in 6 cases, good in 10 cases, fair in 1 case and poor in 1 case. The excellent and good rate was 88.89%. The AOFAS score at the postoperative final follow-up（82.67±13.78）was significantly higher than that of preoperation（51.72±8.28）(P < 0.01), the VAS score at the postoperative final follow-up (0.94±1.39) was significantly lower than that of preoperation (3.56±1.10) (P < 0.01). Conclusion The clinical outcomes of arthroscopic debridement combined with anatomical reconstruction of lateral collateral ligament for treatment of CLAI is satisfactory，which has the advantages of small trauma, simple operation and few complications.