Abstract: Objective To observe the role of arthroscopic acromioplasty in repair of supraspinatus muscle tendon tear. Methods Thirty-four patients with rotator cuff injury accompanying arthroscopy-confirmed full-thickness supraspinatus muscle tendon tear admitted to our hospital from March 2010 to December 2011 were randomly divided into acromioplasty group and non-acromioplasty group(17 in each group).Their shoulder joint function was scored using the CMS system and the UCLA scoring system, respectively. Results No significant difference was found in the CMS and UCLA scores for the shoulder joint between the two groups(P>0.05). Conclusion The effect of arthroscopic acromioplasty is insignificant on repair of rotator cuff injury in patients with supraspinatus muscle tendon tear.