Chronic low back pain is a major spine disorder. In modern societies, besides the economic costs that pain incurs on the patient and the society, the chronic consequences of such pains in the personal, emotional, family, and social lives of the individual have gained the attention of scholars. Since pain sensation is both an emotional and cognitive experience, it is important to use non-pharmacological therapies to reduce the patient's pain. Therefore, the purpose of this study was to investigate the effects of cognitive behavioral hypnotherapy in changing self-efficacy and pain-related beliefs in patients with chronic low back pain. Materials and Methods: A-B single-subject method is used in this research. The statistical population included the adult women with chronic low back pain who referred to the specialized Pain clinic of Labbafinejad Hospital in Tehran in 2017. Convenience method of sampling was used. Four subjects received 8 sessions of individual cognitive-behavioral hypnotherapy. The baseline, intervention and follow-up evaluations were performed using Pain Beliefs and Perception Inventory and the Pain Self-efficacy Questionnaire. Results: Visual analysis of the data charts and comparing the changes in the dependent variable levels based on the median and mean indices, trend, and the percentage of overlapping and non-overlapping data (PND) in the baseline, intervention and follow up stages showed that intervention has been effective in changing the pain beliefs and increasing the self-efficacy of the patients with chronic low back pain. Conclusion: In general, it can be concluded that cognitive-behavioral hypnotherapy can be effective in modifying the pain beliefs and increasing self-efficacy; hence, it can be used as a treatment without side effects regarding the management and control of pain in patients with chronic low back pain.