Objective To compare the efficacies of unilateral biportal endoscopic(UBE)technique and percutaneous transforaminal endoscopic discectomy(PTED)in the treatment of lumbar spinal stenosis.Methods Forty patients who were diagnosed with lumbar spinal stenosis in Chashan Hospital of Dongguan from January 2019 to January 2023 were enrolled in this retrospective study.They were divided into PTED group(n=20)and UBE group(n=20).Perioperative data(operation time,intraoperative bleeding,postoperative hospital stay,degree of decompression and complications)were compared between the two groups.Visual analogue scale(VAS)score and Oswestry dysfunction index(ODI)were collected before surgery and on 3 days,1 month and 6 months after surgery.Results There were no significant differences in the operation time,intraoperative bleeding,or hospitalization time between the two groups(all P>0.05).The incidence of postoperative complications in the UBE group was significantly lower than that in the PTED group(P=0.001).VAS score and ODI of the low back and leg pains in the UBE group were superior to the PTED group at each postoperative time point(all P<0.05).One month after surgery,the UBE group had a more significant increase in the dural sac cross-sectional area and intervertebral foramen area than the PTED group(t=3.842,P=0.003;t=2.469,P=0.006).Conclusion Compared with PTED,UBE has better clinical outcomes,higher degree of decompression,and lower incidence of complications.UBE is a safe and feasible surgical method for the treatment of lumbar spinal stenosis.