Objective To investigate the short-term effectiveness of arthroscopic Lasso-Loop suture combined with Suture Tape augmentation in treatment of lateral ankle instability. Methods A total of 19 patients with lateral ankle instability were enrolled between January 2022 and August 2022, including 11 males and 8 females, with a mean age of 35.5 years (range, 16-68 years). All patients underwent arthroscopic repair of the anterior talofibular ligament (ATFL) using Lasso-Loop suture combined with Suture Tape augmentation. Injury causes consisted of sports injury in 14 cases, sprain in 4 cases, and traffic accident injury in 1 case. There were 6 cases of acute injury and 13 cases of chronic injury. Anterior drawer test was positive in all 19 patients, and varus stress test was positive in 6 patients. Imaging examinations revealed the talar osteochondral lesions in 3 cases, including 2 cases of Outerbridge grade Ⅲ and 1 case of grade Ⅳ. Preoperative American Orthopaedic Foot & Ankle Society (AOFAS) ankle-hindfoot score was 71 (62, 72), and the Kaikkonen ankle injury functional score was 40 (25, 50). Results The incisions in 18 cases healed by first intension; the incision fat liquefaction occurred in 1 patient and recovered after dressing changes. All patients were followed up 12 months. At 12 months after operation, both anterior drawer test and varus stress test were negative. At 6 weeks and 12 months after operation, the AOFAS ankle-hindfoot scores of the affected ankle were 85 (80, 90) and 100 (100, 100), respectively, while the Kaikkonen ankle injury functional scores were 89 (89, 98) and 100 (100, 100), respevtively. All scores significantly improved when compared with preoperative levels and showed a gradual upward trend over time, with significant differences (P<0.05). At 12 months after operation, the AOFAS ankle-hindfoot scores in 19 patients achieved excellent, with an excellent and good rate of 100%. Conclusion For patients with lateral ankle instability, arthroscopic debridement combined with ATFL reconstruction using the Lasso-Loop suture and Suture Tape augmentation can achieve satisfactory short-term effectiveness.