ObjectiveTo investigate early effectiveness of arthroscopic superior fulcrum reconstruction in the treatment of irreparable massive rotator cuff tear (IMRCT). Methods A retrospective analysis was conducted on the clinical data of 24 patients with IMRCT who met the inclusion criteria between January 2020 and April 2022. Among them, there were 11 males and 13 females with an average age of 56.2 years (range, 42-68 years). There were 12 cases of falling injuries, 3 cases of traction injuries, and the other 9 cases had no obvious causes. The disease duration ranged from 1 to 25 months (median, 6 months). The rotator cuff tears were classified as Hamada grade 2 in 18 cases and grade 3 in 6 cases, and Goutallier grade 1 in 3 cases, grade 2 in 20 cases, and grade 3 in 1 case. All patients were treated with arthroscopic superior fulcrum reconstruction. Visual analogue scale (VAS) score, Constant-Murley score, the University of California at Los Angeles (UCLA) score, and the American Shoulder and Elbow Surgeons (ASES) score were recorded before operation and at 1, 3, 6, and 12 months after operation. Results The operations were all successfully completed. The incisions healed by first intention and no related complications occurred. All patients were followed up 12-33 months (mean, 24.6 months). The VAS, Constant-Murley, UCLA, and ASES scores at different time points after operation were superior to those before operation (P<0.05). All of the above indicators further improved with time. Except for no significant difference in VAS and Constant-Murley scores between 6 and 12 months (P>0.05), the differences between the other time points were significant (P<0.05). At 12 months after operation, according to UCLA scoring standard, shoulder joint function was rated as excellent in 4 cases, good in 19 cases, and poor in 1 case, with an excellent and good rate of 96.0%. MRI showed that there was no graft re-tear and the transplanted tendon and bone tunnel healed. Conclusion The arthroscopic superior fulcrum reconstruction for IMRCT can effectively relieve the pain, improve the shoulder range of motion, and restore good shoulder function.