BACKGROUND: The pathophysiologies of Failed Back Surgery Syndrome (FBSS) are epidural adhesion& fibrosis; arachnoiditis, neural encroachment, mechanical instability. Epidural adhesiolysis alleviate back pain through blocking the neural activity of scar area and decreasing the inflammation & edema. There are two methods of adhesiolysis, endoscopic & non-endoscopic adhesiolysis. Present study was aimed to compare the pain relief & side effects between two methods. METHODS: We investigated 86 post-laminectomy patients with low back pain and radiculopathy, who do not relieved with any kinds of conservative treatment. Nerve pathology was demonstrated and epidural fibrosis suspected or proved with MRI examination. Group I was consisted with non-endoscopic 41 patients, and Group II was endoscopic 45 patients. Evaluation included assessment of pain relief (visual analogue scale, VAS), rate of reprocedures and duration of pain relief (VAS < 5) at post-epidural adhesiolysis 2 week, and 1, 2, 6 months. We also looked for complication of adhesiolysis. RESULTS: Statistical analysis (t-test, chisquared test) demonstrated VAS & reprocedure rate was significantly low (P < 0.05) in group II at 6 month and duration of pain relief (VAS < 5) was more prolonged in group II. One patient in each groups complained skin eruption and pruritus, and one patient of group II was proved epidural abscess and one patient of group I complained headache. CONCLUSIONS: Endoscopic and non-endoscopic epidural adhesiolysis are effective and safe in patients, who was not relieved the symptoms with conservative treatment, but endoscopic epidural adhesiolysis is more recommendable because its more prolonged effect.