Lumbar spinal stenosis is common among the elderly, and its surgical treatment includes open surgery and minimally invasive surgery. Percutaneous endoscopic lumbar discectomy is the first-choice minimally invasive surgery for this condition because of its small wound, mild pain and rapid recovery. The procedure is performed via either percutaneous interlaminal or percutaneous transforaminal approach with their own indications, advantages and disadvantages. Clinically, choosing the optimal approach based on pathological types of lumbar spinal stenosis determines the success of the operation.