Context: A simulated horseback riding (SHR) exercise is effective for improvement of pain and functional disability, but its comparative effectiveness with the other is unknown. Objective: The authors aimed to demonstrate the effect of a SHR exercise in people with chronic low back pain. Design: A randomized controlled trial. Settings: Community and university campus. Participants: A total of 48 participants with chronic low back pain were divided into 2 groups, and SHR exercises (n = 24) or stabilization (STB) exercises (n = 24) were performed. Interventions: The exercises were performed for 30 minutes, 2 days per week for 8 weeks. Main Outcome Measures: Numeric rating scale, functional disabilities (Oswestry disability index and Roland–Morris disability), and fear-avoidance beliefs questionnaire (FABQ) scores were measured at baseline and at 4 weeks, 8 weeks, and 6 months. Results: A 2-way repeated analysis of variance identified that between-group comparisons showed significant differences in the FABQ related to work scale (F = 21.422; P = .01). There were no significant differences in the numeric rating scale (F = 1.696; P = .21), Oswestry disability index (F = 1.848; P = .20), Roland–Morris disability (F = 0.069; P = .80), and FABQ related to physical scale (F = 1.579; P = .24). In within-group comparisons, both groups presented significant differences in numeric rating scale (both SHR and STB after 4 wk), Oswestry disability index (both SHR and STB after 6 mo), and Roland–Morris disability (SHR after 6 mo and STB after 8 wk) compared with baseline values. In FABQ-related physical (SHR after 4 wk) and work scales (SHR after 6 mo), there were only significant differences in the SHR compared with baseline values. Conclusions: SHR exercise for 8 weeks had a greater effect than STB exercise for reducing work-related FABQ. The SHR exercise performed in a seated position could substantially decrease pain-related fear disability in young adults with chronic low back pain.