Background: Lumbar stabilization exercise and gluteal muscle strengthening exercises are widely used to treat for lower back pain patient. The present study aimed to compare the effects of lumbar stabilization exercise and gluteal muscle strengthening exercises on chronic lower back pain with lumbar spine instability, with regard to pain intensity, disability, and psychosocial factors. Methods: Among 53 patients with chronic lower back pain, those with spine instability were selected using 5 examination tests. The selected 28 patients were randomly assigned to lumbar stabilization exercise group (LSE, n=15) and gluteal strengthening exercise group (GSE, n=13). Each group performed the corresponding exercise for 40 minutes, twice a week for 4 weeks. To analyze and compare the effects, pain intensity, the level of low back disability, and psychosocial factors were assessed before and after intervention. Results: There was significant difference in lower back pain intensity between the two groups before and after intervention. The change in low back disability was significant in the GSE group alone following intervention (p<.05), but no other significant difference was found between the groups. Among psychosocial factors, the changes in the fear-avoidance beliefs questionnaire (FABQ)-physical activity and FABQ-total were significant in the LSE group alone following intervention (p<.05). However, no significant difference were found in these factors between the two groups before and after intervention. Conclusions: LSE and GSE for lower back pain with lumbar spine instability showed no significant difference for pain intensity, physical disability, or psychosocial functioning.