[Objective] To explore the effect of hydrogen-oxygen mixture on the shoulder joint function of patients with rotator cuff injury after surgery. [Methods] From February 2020 to October 2021, a total of 60 patients who were undergoing unilateral arthroscopic rotator cuff repair with for rotator cuff injury were included in this study. According to the results of patient-doctor communication preoperatively, 30 patients in the hydrogen-oxygen group receiced hydrogen-oxygen mix gas, while the remaining 30 patients in the oxygen group was given oxygen. The document regarding to clinical presenations, follow-up outcomes and postoperative inflammatory factors were collected and compared. [Results] All patients in the two groups had arthroscopic rotator cuff repair surgery completed successfully. There was no significant difference in the operation time , in mean arterial pressure and heart rate post-intubation 30min in both groups (P>0.05). In term of analgesic effect, the hydrogen-oxygen group had significantly lower VAS score at matching time point postoperatively (P<0.05). What is more, the Constant-Murley and UCLA score increased significantly over time in all the 2 groups (P<0.05) , which proved significantly better in the hydrogen-oxygen group at the corresponding time point (P<0.05) . Regarding to inflammatory factor, the hydrogen-oxygen group had significantly lower IL-6 and TNF-a levels from 1 to 12 weeks after operation than the oxygen group (P<0.05) . [Conclusion] Hydrogen-oxygen mix gas can alleviate shoulder pain and improve functional recovery of shoulder joint after arthroscopic.