L5-S1 disc has always been a difficult disc to target by rigid endoscope because of anatomical limitations. In this study, we have described the technique to overcome difficulty faced during endoscopic disc decompression of high-grade inferior migrated disc at L5-S1. We performed percutaneous endoscopic inter-laminar lumbar discectomy (PEILD) for removal of high grade inferiorly migrated disc and preserved the functional structures. After institutional review board approval, details of the patient with high-grade inferior migration at L5-S1 disc were reviewed. The patient was operated by a single specialist with use of the percutaneous endoscopic inter-laminar technique for high-grade inferior migrated extruded disc. Description of our technique & result is the focus of this study. The average VAS score was reduced from 9 pre-operatively to 3 post-operatively & to 1-2 within 2 weeks. Post-operative plantar flexion of foot improved from 2 to 4 immediately and up to 5 within 2 weeks. Ankle jerk reflex improved from 1+ to 2+. The pain severity score on BPI reduced from 9 to 3 postoperatively. Post-operative MRI showed that the high grade inferiorly ruptured disc had been successfully removed. We obtained excellent results in treating inferior extruded disc at L5-S1 using endoscopic inter-laminar approach. Inter-laminar endoscopic discectomy can be used as a safe yet minimally invasive technique for the treatment of lumbar radiculopathy in the setting of a high grade inferior migrated lumbar disc herniation.