Abstract:[Objective] To compare the clinical efficacy of Delta endoscopic decompression versus unilateral biportal endoscopy (UBE)counterpart for lumbar spinal stenosis (LSS). [Methods] A retrospective study was conducted on 100 patients who had LSS treated by endo-scopic decompression from January 2022 to June 2023. According to preoperative doctor-patient communication, 46 patients were treatedwith Delta endoscopic decompression, while other 54 patients received UBE decompression. The perioperative, follow-up and imaging datawere compared between the two groups. [Results] The Delta group proved significantly superior to the UBE grpup im terms of operative time[(94.2±15.6) min vs (102.3±13.9) min, P=0.007], the incision length [(2.2±0.2) cm vs (1.3±0.1) cm, P<0.001] and intraoperative fluoroscopyfrenquency [(3.5±0.4) times vs (6.4±0.6) times, P<0.001], although there were no significant differences in intraoperative blood loss, the bedrest time, hospital stay, quality of incision healing and incidence of complications between the two groups (P>0.05). Compared with those pre-operatively the low back pain and leg pain VAS scores, as well as ODI were gradually improved in both groups 3 months after surgery and atthe last follow-up (P<0.05), whereas which were not statistically significant between the two groups at any time points accordingly (P>0.05).In addition, there was no significant difference in the time to regain full weight-bearing activity between the two groups (P>0.05). As for im-aging evaluation, the vertebral canal area and dural sac cross-sectional area were increased in both groups at the last follow-up comparedwith those preoperatively (P<0.05), but there was no significant difference between the two groups at any matching time points (P>0.05).[Conclusion] Both Delta endoscopy and unilateral biportal endoscopy used lumbar canal decompression do achieve satisfactory clinical con-senquence for lumbar spinal stenosis. In comparison, the Delta endoscopy is superior to the UBE in terms of operation time, surgical incisionand fluoroscopy times.