The etiology of rotator cuff tears includes trauma, degeneration and infection, and it is a common cause of shoulder pain and dysfunction. It occurs in adults over 45 years of age. Treatment options include conservative treatment, incisional repair, small incisional incisional repair, and total arthroscopic repair. The indications for arthroscopic repair include symptomatic rotator cuff tears (pain and dysfunction), non-irreparable massive rotator cuff tears, but other factors must be considered such as the patient’s general condition to tolerate the procedure, the patient’s requirements and expectations, the surgeon’s assessment of postoperative functional recovery, and the presence of combined osteoarthritis or significant upward displacement of the humeral head. Contraindications to arthroscopic repair include: active infection, permanent innervation loss, and severe glenohumeral osteoarthritis. Relative contraindications include poor or unpredictable prognosis after repair, severe atrophy of the supraspinatus and infraspinatus muscles with <75% fattening, inability of the patient to cooperate with postoperative rehabilitation, and significant displacement of the humeral head with bony changes on imaging. The position of the surgery can be selected according to personal preference in the beach chair position followed by lateral recumbency, with traction weight of approximately 5-10 pounds in lateral traction, 40° of abduction and 20° of forward flexion of the affected limb, and intraoperative application of a heating blanket to prevent the occurrence of hypothermia. Anesthesia can be used as interosseous sulcus, general anesthesia, or both. The use of interosseous sulcus alone is only suitable for patients with a short operative time and good general condition. If the operation is long, the patient may have significant intraoperative neck edema, which may cause respiratory distress, and the blood pressure needs to be controlled between 90-110 mmHg during the operation, general anesthesia is recommended. In addition to the conventional arthroscopic system, grinding drill, planer, and radiofrequency, a water injection and pressure pump system is needed during the operation, and the water injection pressure should be controlled at 50-70 mmHg, and the operation time should be controlled within 2 hours to avoid excessive edema of the tissue. In addition there should be a variety of angles of over the line device to choose and use, now each company has its own characteristics of over the line device to choose, in addition a good assistant in surgery is very important. There are various suture anchors available, metal, plastic, absorbable, and different diameter anchors can be used depending on the site, bone quality and space size. The tensile strength of the anchor nails differs greatly from design to design. The tensile strength of sutures of the same diameter increases by almost a factor of one, and the chance of rotator cuff repair failure due to suture fracture is decreasing. Also the arthroscopic knot tying technique affects the strength of the postoperative rotator cuff fixation. In terms of suture selection, we commonly use simple sutures, mattress sutures, and edge sutures, etc. In terms of fixation methods, microscopic sutures have gradually developed from single-row suture fixation in the past to a double-row fixation method, and even a three-row fixation method has been proposed. Double-row fixation can increase the contact area of the tendon bone, and contact pressure, and promote healing, but the literature reports of the effect of different methods vary. Most retrospective studies have reported no significant differences in clinical outcomes between single- and double-row fixation. A prospective randomized study showed 40 single-row and 40 double-row cases with no clinical differences. A study of rotator cuff footprint coverage showed 52.7% uncovered with single-row fixation, whereas complete coverage could be achieved with double-row fixation. Single-row fixation is currently recommended for partial tears or small tears and double-row fixation for large tears Arthroscopic release is a very important step in the surgical operation, especially for microscopic repair of large rotator cuffs where adequate release is necessary and rostral acromion shaping should be considered if the distance between the rostral acromion and the subscapularis is less than 7 mm. And it is still controversial whether acromioplasty is necessary for the acromion. Acromioplasty can weaken the stop of the deltoid and create a scar between the subacromial bone trauma and the repaired rotator cuff, but if the acromion has definite hyperplasia, bony bulge, or subacromial impingement, acromioplasty should be performed at the same time. There are many factors that affect the healing after rotator cuff repair, such as the angle and depth of the suture anchor implantation. If the camber angle is too small and the depth is too deep, the suture anchor will be easily pulled out and loosened. Adequate intraoperative release of adhesions can reduce the tension of the tendon after suturing. Adequate preparation of the tendon-bone junction (clearing the tendon edge, preparing the bone bed to bleed, etc.) may also promote healing. The use of different sutures to increase tendon bone contact area and pressure, as well as relatively conservative postoperative rehabilitation will promote tendon bone healing in the rotator cuff, thus reducing the failure rate.