OBJECTIVE: This study compared the efficacy and safety of unilateral biportal endoscopic (UBE) decompression and transforaminal route percutaneous endoscopic lumbar decompression (PELD) for lumbar spinal stenosis (LSS), assessing 1-year clinical outcomes. METHODS: A total of 120 patients (64 UBE, 56 PELD) diagnosed with LSS in 2021 were evaluated. Perioperative outcomes included overall operation time, extracanal operative time, intracanal decompression time, incision length, fluoroscopy time, estimated blood loss, preoperative and postoperative day 3 hb levels, length of post-operative hospital stays, total expenses, postoperative complications. Clinical outcomes were measured using visual analog scale (VAS) for back and leg pain, Oswestry disability index (ODI) for physical impairment and the modified MacNab criteria. RESULTS: Results showed no demographic differences between groups. UBE had shorter total operation and intracanal decompression times but longer extracanal operative time than PELD (all CONCLUSION: Both techniques were safe, but PELD posed a higher risk of reoperation due to decompression failure. UBE demonstrated advantages in decompression efficiency and clinical outcomes despite longer incision length and greater blood loss.