Objective To investigate arthroscopic treatment for acute acromioclavicular dislocation by using Twin Tail TightRope combined with distal joint capsular repair. Methods The clinical data of 40 patients with acromioclavicular dislocation treated between February 2016 and December 2017 were retrospectively analyzed. The patients were divided into arthroscopic group (20 cases, using arthroscopic Twin Tail TightRope combined with distal joint capsular repair for anatomical repair of stable structure of acromioclavicular joint) and control group (20 cases, treated with clavicular hook plate internal fixation) according to different surgical methods. There was no significant difference in gender, age, cause of injury, Rockwood classification, time from injury to operation, preoperative visual analogue scale (VAS) score and Constant score between the two groups (P>0.05), which were comparable. Postoperative VAS score and Constant score were used to assess shoulder function and re-dislocation was also observed. Results The incisions of the two groups healed by first intention, and no early postoperative complications occurred. All patients were followed up 12-18 months (mean, 13.5 months). Postoperative X-ray films showed good anatomical reduction in both groups, but the clavicular hook had a presense in the subacromial space in control group. All patients in arthroscopic group achieved satisfactory shoulder function and returned to work after operation; there was no obvious pain, no complications such as exposure of implant after operation, and no need to remove the implant. In the control group, 4 patients had obvious subacromial impingement pain after operation, and 1 patient had re-dislocation after removal of internal fixator at 1 year after operation; the rest had no complications related to internal fixation, and the internal fixators were removed at 1.0-1.5 years after operation, without re-dislocation. The VAS score and Constant score at 3 months and 1 year after operation in both groups significantly improved when compared with those before operation, and further improved at 1 year after operation (P<0.05). The VAS score and Constant score at 3 months and 1 year after operation in arthroscopic group were significantly better than those in control group (P<0.05). Conclusion Arthroscopic treatment for acute acromioclavicular joint dislocation by using Twin Tail TightRope combined with distal capsular repair is more effective than traditional incision surgery and can obtain more satisfactory results in patient compliance and function recovery because of minimally invasive surgery.