To help clarify the comparative effects of percutaneous endoscopic discectomy and microsurgical discectomy in the treatment of lumbar disc herniation, the authors studied 37 consecutive patients with discogenic symptoms who had not responded to conservative treatment. Their indications are restricted to discogenic root compression with"contained"or small"noncontained"lumbar disc. Patients with sequestrated disc, spinal stenosis, or spondylolisthesis were excluded. All patients underwent magnetic resonance imaging and if the radiological interpretation was confused with extruded migrated disc, a discogram was also obtained. Of the 37 patients, 18 underwent percutaneous endoscopic discectomy and 19, microsurgical discectomy. In order to compare the efficacy of the two methods, both groups were investigated. Disc herniations were located at L4-5(24 patients), L5-S1(11 patients), or L4-5 and L5-S1(2 patients). With regard to age and sex distribution, preoperative complaints, and clinical symptoms, there were no differences between the two groups. At the last follow-up evaluation after percutaneous endoscopic discectomy, low back pain had disappeared in three patients(17.6%), sciatica in nine(50.0%), sensory deficits in two(16.7%), motor deficits in three(42.5%), and reflex differences in one (50%). After microsurgical discectomy, low back pain had disappeared in one patient(5.6%), sciatica in nine(47.4%), sensory deficits in five(33.3%), motor deficits in six(66.7%), and reflex differences in three(75.0%). In 83.3% of patients in the percutaneous endoscopic discectomy group, the outcome was successful(excellent or good result), compared with 78.9% of those who had undergone microsurgical discectomy. One patient in the percutaneous endoscopic discectomy group suffered from discitis. For patients with"contained"or slight subligamentous lumbar disc herniations, percutaneous endoscopic discectomy offers a surgical alternative.