Purpose: The purpose of this study was to investigate the effects of lumbar stabilization exercise on balance ability in patients with adolescent idiopathic scoliosis. Methods: This study was one group pretest-posttest design. Twenty young idiopathic scoliosis patients were recruited for this study. They had the lumbar stabilization exercise program for 40 minutes a day, three times per week for 3 weeks. The lumbar trunk muscle endurance test and clinical balance tests (functional forward reach, functional lateral reach, Fukuda 50-stepping, one leg standing with eyes open and eyes closed) were measured before and after the lumbar stabilization exercise. Results: There were significant differences between pre-and post-test in absolute value of the difference between right and left lateral reach, distance of Fukud 50-stepping and one leg standing on the each side with eyes closed(p<.05). The results showed that the lumbar trunk muscle endurance significantly increased(p<.05). Conclusion: In this study indicated that the lumbar stabilization exercise was effective on balance ability and lumbar trunk muscle endurance in patients with young idiopathic scoliosis.