For lumbar disc herniation, conventional laminectomy and discectomy were used for a long time. Since chemonucleolysis was introduced as a treatment modality of lumbar disc herniation in 1964, other various minimally invasive surgical techniques like Percutaneous Nucleotome, Arthorscopic Microdiscectomy and laser discectomy were developed to minimize postoperative discomfort and morbidity. In conventional surgery with laminectomy, there is no limitation for surgical procedures, and the surgical result is very excellent over 90%. But it causes a postoperative wound pain due to muscle injury and a possibility of nerve root injury. Minimally invasive surgical techniques has advantages of minimal postoperative pain and morbidity. Also it has limitations of narrow indication like soft disc herniation without bony stenosis and comparatively low surgical result about 70%. Recently a new minimal invasive endoscopic discectomy system was developed which has advantages of conventional laminectomy and minimally invasive surgical techniques. It can decompress the nerve root like conventional open surgery and has the benefits of small incision, limited tissue disruption and faster recovery time. We have had 3 cases experiences of MicroEndoscopic Discectomy(MED) system in lumbar disc herniations and got excellent clinical result.