Introduction. Exercises have been shown to relieve symptoms in non-specific chronic low back pain (NSCLBP) patients. Aim. This study compared the effects of cognitive behavioural therapy (CBT) and core stabilization exercises (CSE) on pain-related disability, psychological status and sleep disturbance in patients with NSCLBP. Material and methods. This randomized controlled trial involved a total of thirty-seven (37) participants. They were randomly allotted into three groups [CBT (11), CSE (14) and control (12)]. The intervention was done once per week for duration of 60 minutes for the CBT group, 30 minutes for CSE group and 10 minutes for the control group twice per week for 8 consecutive weeks. Assessment of outcome was done at baseline, 4 weeks and 8 weeks. Data were analyzed using statistical package for social science version 25 at alpha level of less than 0.05. Results. The results of this study showed that there was significant improvement in the level of pain-related disability (p= 0.001), level of anxiety (p =0.001), depression (p = 0.01, p = 0.001, p =0.001) and sleep disturbance (p = 0.001) in all the groups (CBT, CSE, control) post treatment. Conclusion. CBT and CSE are both effective in the treatment of pain-related disability, sleep disturbance, and psychological status of NSCLBP patients.