Background Correcting false cognitions and establishing preventive behaviors in patients with chronic low-back pain can improve self-efficacy and self-discovery of these patients against the physical and psychological consequences of chronic back pain through reinforcing thoughts and constructive behaviors. Objectives This study aimed to investigate the effectiveness of cognitive-behavioral training in self-efficacy, self-discovery, and pain perception of patients with chronic low-back pain. Methods Based on a quasi-experimental design, 40 patients with chronic low-back were selected through purposive sampling and assigned into two groups of intervention (n = 20) and control (n = 20). After administering the pain self-efficacy (PSE) scale, the self-discovery scale (SDS), and the pain perception questionnaire (MPQ) to both groups, the intervention group received the cognitive-behavioral training while the control group did not receive the intervention. The post-test was performed on both groups and the data were analyzed using SPSS. Results The scores of pain self-efficacy and self-discovery (self-awareness and acceptance, commitment and attraction, transcendence and development, and personal growth) were higher in the intervention group than in the control group (P < 0.01). The highest increase with an effect size of 0.514 was related to the self-awareness and acceptance subscale. In addition, the pain assessment perception was the only reduced subscale among the other dimensions of pain perception (P < 0.01). Conclusions Psychosocial complementary therapies can provide patients suffering from chronic pain with better physical and mental conditions to have a higher quality of life.