Background: In general, the outcomes of arthroscopic repair for superior labrum anterior to posterior lesions (SLAP) are favorable, however, persistent pain and limitation of motion are not rare complications. One of the possible cause is a "knot-ache". This study evaluated the results of reoperation of symptomatic recurrent SLAP lesions and asked whether the knot is associated with postoperative complications. Methods: Between 2005 and 2015, a total of 11 patients who had undergone arthroscopic SLAP repair were reoperated for recurrent symptomatic SLAP lesion. By retrospective chart review, operative findings, the visual analogue scale for pain (pVAS), the range of motion (ROM), and functional scores were analyzed. Results: The mean age of the study participants was 38.3 years, and the mean follow-up period was 42.5 months. In the primary operation, there were nine cases of repairs with conventional knot-tying anchors and three cases with knotless anchors. Impingement of the knots during abduction and external rotation of the shoulder was observed in the all cases with knot-tying anchors. The mean pVAS, ROM, and functional scores significantly improved with reoperation. At the final follow-up, the mean satisfaction VAS was 8.3. Conclusions: The knots of suture anchor maybe a possible etiology of the pain, which we termed a "knot-ache". Considering that reoperation is performed due to pain after primary repair, the use of knotless suture anchor may have benefits of eliminating one of possible cause, "knot-ache". Therefore, authors suggest the use of knotless anchors during reoperation for recurrent or recalcitrant pain after primary SLAP repair. (Clin Shoulder Elbow 2017;20(2):68-76)