OBJECTIVE: There are various surgical approaches to far-lateral lesions in the L5-S1 intervertebral space. Of these is the validity of a paramedian tangential approach is being investigated in this study. METHODS: A retrospective study was conducted on 25 patients who had been diagnosed as having a far-lateral L5-S1 disc herniations, osteophyte, costal process hypertrophy, and had undergone a paramedian tangential approach from November 1999 through December 2003. The degree of symptoms and improvement were compared via the visual analog pain scale, before and after surgery. RESULTS: This study included 4 males and 21 females with a mean age of 62+/-11.8 years old. The average follow-up period after surgery was 8.2+/-2.7 months. The visual analog pain scale taken before surgery was 6.7+/-1.1 points, while the post-surgical scale was 2.4+/-0.9 points showing a significant decrease (p<0.05). There were no complications that developed during surgery. CONCLUSION: A paramedian tangential approach is less invasive in the soft tissue than that of the median approach. This approach may effectively reduce nerve root compression and expand intervertebral foramens, and is devoid of the risk of spinal instability after surgery. The authors suppose that a paramedian tangential approach is quite an effective technique to relieve compression in the far-lateral L5-S1 intervertebral space.