Introduction: It is proven that obesity compromises the quality of life, generating disability and reducing longevity. Among the most common comorbidities are musculoskeletal disorders, with a diagnosis of chronic low back pain. In view of the failure of conservative treatment of obesity, bariatric surgery is indicative. Objective: To analyze the effects of bariatric surgery on chronic low back pain. Materials and Methods: This was a descriptive cross-sectional study analyzing pain and quality of life through the application of the Visual Analogue Scale (VAS) and the SF-36 Quality of Life Questionnaire in individuals, both genders, age over 18 years old, clinical diagnosis of chronic low back pain submitted to bariatric surgery, with a postoperative time greater than 12 months. Results: 32 individuals were assessed, 71.87% women, mean age of 36.6 (+/- 11.31) years, mean postoperative time of 32.4 (+/- 12.82) months, mean reduction in BMI from 46.4kg/m(2) to 29.1kg/m(2). In the analysis of pain, through the application of VAS, there was a decrease in the symptom from 7.25 (+/- 1.45) to 2.46 (+/- 1.74) in the postoperative period. The results of the SF-36 Questionnaire, comparing pre and postoperative periods, showed significance in the items functional capacity (36.2-88.5), limitation by physical aspect (23.4 - 89.8) pain (31.5 - 91, 6), general health status (39.6 - 87.9) and vitality (33.2 - 85.7). Conclusion: Obesity is strongly related to the symptoms of chronic low back pain, and bariatric surgery is an effective alternative for weight loss, pain reduction, resulting in considerable improvement in quality of life.