Serratus posterior superior intercostal plane block (SPSIPB) is a novel technique that provides analgesia in shoulder, hemithorax and in the back of the neck. In this study, the efficacy of this block on postoperative pain and quality of recovery is reported in ten consecutive patients who had undergone reduction mammoplasty. Blocks were performed bilaterally with 30 ml 0.25 % bupivacaine for each side, at the end of surgery. Cumulative tramadol consumption and numerical rating scale (NRS) scores during rest (static) and coughing (dynamic) were assessed within the first postoperative 24 hours. Mean total tramadol consumption was 39 ±9.94 mg. NRS scores above 4 were observed in 5 patients in the dynamic NRS assessment at the postoperative 1st hour, while static and dynamic NRS scores were ≤4 at other durations. SPSIPB may play a part in postoperative multimodal analgesia following mammoplasty in the future and may reduce total analgesic consumption. Key Words: Serratus posterior superior intercostal plane block, Reduction mammoplasty, Breast surgery, Postoperative analgesia.