Video-assisted thoracoscopic surgery (VATS) is a minimally invasive procedure performed through small thoracic incisions, but postoperative pain remains significant due to tissue and rib trauma. Poorly controlled pain may lead to chronic postoperative pain; therefore, optimal analgesia is essential. According to PROSPECT guidelines, erector spinae plane block (ESPB) or paravertebral block (PVB) are recommended for VATS. The recently defined serratus posterior superior intercostal plane block (SPSIPB) provides analgesia between C3-T10 levels, but its efficacy compared with ESPB has not been studied. This study aims to compare postoperative analgesic efficacy and patient satisfaction between ESPB and SPSIPB in VATS patients.