Abstract:[Objective] To compare the clinical outcomes of the unilateral biportal endoscopic discectomy (UBED) versus Quadrantchannel discectomy (QCD) in the treatment of single-level lumbar disc herniation. [Methods] A retrospective study was performed on 61 pa- tients who were treated by minimally invasive surgeries for single-segment lumbar disc herniation in our department from June 2021 to De- cember 2021. According to doctor-patient communication, 32 patients were treated by UBED, while the other 29 patients were by QCD. The perioperative period, follow-up and imaging data were compared between the two groups. [Results] All patients in both groups had corre- sponding surgical procedures performed successfully with 1 case of dural tear in each group that not leaded serious adverse consequences. Although the UBED group consumed significantly longer operative time [(58.3±7.0) min vs (42.0±6.7) min, P=0.039] and more intraoperative fluoroscopy [(4.5±1.0) times vs (3.6±1.2) times, P=0.003] than the QCD group, the former proved significantly superior to the latter in terms of total incision length [(2.7±0.2) cm vs (3.3±0.2) cm, P<0.001], intraoperative blood loss [(45.8±12.6) ml vs (56.2±13.5) ml, P=0.003], and postoperative walking time [(2.2±0.5) days vs (2.9±0.7) days, P<0.001]. All patients in both groups were followed up for 12~14 months with a mean of (12.8±0.7) months, and the UBED group resumed full weight-bearing activity significantly earlier than the QCD group [(6.0±1.1) weeks vs (6.7±1.1) weeks, P=0.023]. The VAS scores for low back pain and leg pain, as well as ODI scores significantly decreased in both groups over time (P<0.05), which proved not statistically significant between the two groups at any time point accordingly (P>0.05). Regard- ing imaging, the spinal canal occupying rate of the involved segment was significantly decreased in both groups after surgery and at the last follow-up compared with that preoperatively (P<0.05), while the intervertebral height and the Cobb angle of lumbar lordosis remained un- changed (P>0.05). There were no significant differences in the above imaging indexes between the two groups at any matching time point (P>0.05). [Conclusion] Both surgical techniques are safe and effective minimally invasive methods for the treatment of lumbar disc herniation. Although UBED consumes longer operation time and more fluoroscopy times, it takes advantages of less trauma and faster postoperative re- covery over the QCD.