Aim:L5/S1 Adolescent lumbar disc herniation (ALDH) is usually ignored for its low incidence. Recently, percutaneous endoscopic procedures have been widely used. The aim of the study was to investigate the surgical techniques and clinical outcomes of percutaneous endoscopic interlaminar discectomy (PEID) in the treatment of L5/S1 (ALDH). Material and Methods:A retrospective study was performed between May 2012 to September 2014, which included 23 adolescent patients who underwent PEID for L5/S1 lumbar disc herniation. Ten females and 13 males were included, with a mean age of 15.4 years and a mean BMI of 25.1 kg/m2. The pre- and post-operative visual analogue scale (VAS), Japanese Orthopaedic Association (JOA), and modified MacNab scores, as well as perioperative data, were collected. Results:The mean follow-up period was 19.7 months. The average operation time and hospital stay were 80.9±7.3 min and 5.8±1.2 d, respectively. During follow-up, the VAS for back and leg pain decreased significantly, and JOA scores greatly increased (P<0.05). In terms of modified MacNab criteria, 86.9% of patients showed excellent or good results. After surgery, two patients complained of leg numbness, and another patient underwent a subsequent open discectomy due to recurrent disc herniation. Conclusion:Considering specific anatomical peculiarities and expectation for rapid recovery, PEID is a safe and effective minimally invasive technique for ALDH at the L5/S1 level.