PURPOSE: This study was performed to investigate the differences in the expression of matrix metalloproteinase-3 in degenerative scoliosis compared with other degenerative disc disease of the spine. MATERIALS AND METHODS: The intervertebral disc materials were obtained during discectomies. Six, 13 and 12 cases of herniated nucleus pulposus, spinal stenosis and degenerative lumbar scoliosis, respectively, were included in the experimental group. The expression of MMP-3 was evaluated three times that of the means, in the immunohistochemical staining, western blotting using anti human MMP-3 antibody and RT-PCR with MMP-3 primer, respectively. RESULTS: On the immunohistochemical stains, extensive and strong staining was noted in the discs of degenerative lumbar scoliosis compared to those with spinal stenosis and HNP. In the western blotting, greater expression of MMP-3 was noted in the discs of degenerative lumbar scoliosis (mean optical density: 20.68) than in other degenerative disc diseases (SS: 6.24, HNP: 2.0). In the RT-PCR, a similar result was shown (DLS: 62.1, SS: 27.4 and HNP: 10.4). There were statistically significant differences between degenerative lumbar scoliosis and degenerative disc disease (p<0.05). CONCLUSION: Rapid degeneration of the intervertebral disc might be an important factor in the pathogenesis of degenerative lumbar scoliosis. MMP-3 could be a key enzyme for the rapid degeneration of the intervertebral discs, especially in degenerative lumbar scoliosis.