Background: The current surgical techniques for repairing Ellman III partial articular supraspinatus tendon avulsion (PASTA) is mainly tear completion followed by repair and in situ transtendon repair, and both techniques have been proven to have good clinical effects. In situ transtendon repair is more widely used because of its high performance in preserving the integrity of the bursal side supraspinatus tendon. However, there is still some scope for improvement. Our purpose was to compare the clinical outcomes of the all-inside repair technique and in situ transtendon repair for Ellman III PASTA.Methods: A retrospective comparative study was conducted on 56 patients who suffered from Ellman III PASTA and underwent rotator cuff repair; 28 patients were treated with the all-inside technique (group A), and 28 patients were treated with the transtendinous tech-nique (group B). All patients were followed up for at least 2 years. The visual analog scale (VAS), Constant, and American Shoulder and Elbow Surgeons (ASES) scores were used to evaluate the patient's shoulder joint function before surgery, 1 month and 3 months after surgery, and at the last time of follow-up.Results: Group A showed superiority in pain and functional improvement 1 month after the operation: the VAS score, 2.8 +/- 0.3 in group A vs. 4.7 +/- 0.4 in group B (P = .042); Constant score, 73 +/- 5 in group A vs. 60 +/- 6 in group B (P = .038); and ASES score, 75 +/- 5 in group A vs. 58 +/- 7 in group B (P = .043), whereas there was no statistical difference in group B. However, 3 months after surgery and at the last follow-up, the VAS, Constant, and ASES scores in both groups were significantly improved (P <.01), and there was no significant statistical difference between the groups (P > .05). Magnetic resonance imaging showed that the repaired rotator cuff tendon-bone healed well; at the last follow-up, all patients were in good function, the pain was completely relieved, and no revision was performed in both groups.Conclusion: Arthroscopic repair of Ellman III PASTA provided satisfactory functional improvements and pain relief regardless of the all-inside and in situ transtendon repair techniques. However, the all-inside repair technique is more beneficial due to its dual function in preserving the intact bursa and avoidance of uneven tension of the articular side, which is advantageous to early postoperative rehabilitation.Level of evidence: Level III; Retrospective Cohort Comparison; Treatment Study (c) 2022 Journal of Shoulder and Elbow Surgery Board of Trustees. All rights reserved.