Abstract:[Objective] To compare the clinical outcomes of unilateral biportal endoscopy (UBE) versus percutaneous interlaminar endo- scopic discectomy (PIED) for lumbar lateral recess stenosis accompanied with disc herniation. [Methods] A total of 60 patients received en- doscopic surgeries for single-segment lumbar lateral recess stenosis accompanied by disc herniation in our hospital from November 2018 to November 2020. Based on preoperative doctor- patient communication, 30 patients had UBE performed, while the other 30 patients had PIED conducted. The documents regarding to perioperative period, follow-up and laboratory and imaging examinations were compared be- tween the two groups. [Results] The UBE group consumed significantly shorter operation time, whereas had significantly longer incision than the PIED group (P<0.05) , although there were no statistical differences between the two groups in terms of blood loss, fluoroscopy times, time to return walking postoperatively, healing grade of incision and hospital stay (P>0.05) . There was no significant difference in the time to re- sume full-weight bearing activity between the two groups (P>0.05) . As time went during follow-up lasted for (21.48±6.82) months on an aver- age, the VAS scores of low back pain and leg pain, as well as ODI scores decreased significantly (P<0.05) , whereas the JOA scores increased significantly in both groups (P<0.05) . However, there were no statistically significant differences in abovementioned items between the two groups at any matching time points (P>0.05) . In terms of auxiliary examinations, the blood myoglobin, anteroposterior diameter of lateral re- cess and the area of the involved spinal canal increased significantly (P<0.05) , while the intervertebral space height remained unchanged postoperatively compared with those preoperatively in both groups (P>0.05) , which were not statistically significantly different between the two groups at any corresponding time points (P>0.05) . [Conclusion] Both UBE and PIED are effective and minimally invasive techniques for lumbar lateral recess stenosis accompanied with disc herniation, but UBE takes an advantage of shortening operation time.