INTRODUCTIONThe prevalence of obesity among adolescents is rising in the recent decades specifically in developed countries around the world. Childhood obesity can lead to adulthood obesity, which reduces lifespan and decreases the quality of life. 1 Nowadays, the incidence of obesity at all ages have been doubled in the developing countries including India. According to a report from urban South India, 21.4 % of boys and 18.5% of girls aged 13-18 years were overweight or obese. 2 The prevalence of obesity among school children in India has been reported between 5.74% and 8.82%. 3,4 Overweight childhood and adolescent have augmented risk of being overweight as adults. The various factors like genetics, behavior, and family environment play a role in childhood overweight. Childhood overweight increases the risk for certain medical and psychological conditions. 5 Multiple ABSTRACT Background: Morbid obesity has risen in an alarming rate in children and adolescent patients. Bariatric surgery is playing an increasing role in pediatric surgery. However, current evidence is limited regarding its safety and outcome. The aim of this study is to evaluate the efficacy of Mini/One Anastomosis Gastric Bypass (MGB/OAGB) in treating obesity and its co-morbidities among childhood and adolescent patients. Methods: A retrospective study was conducted of patients aged <18 who underwent OAGB/MGB in this series at Mohak Bariatric and Robotic Surgery Center (MBRSC) is a tertiary-care center. The major outcome measures were percent excess body weight loss (%EBWL) over a 2-year follow-up period, resolution of co-morbidities, and occurrence of complications. Results: A total of 20 childhood and adolescent patients underwent the procedure, of which, 11 (55.0%) of being males. The patients had a median age of 15 years (range 6-18). The average age was 15.5±3.17 year (range 6-18 years). The initial average weight and BMI was 112.13±26.52 Kgs and 40.86±8.17 kg/m 2 respectively. Postoperative average weight loss was 28 kgs, 33 kgs and 37.2 kgs in 6 months, 1 st year and 2 nd year respectively. The %EBWL at 1st and 2nd years was 75% and 80% respectively. Overall post-operative complication rate was 5.0% (two cases) of which one had gastroesophageal reflux and the other had protein caloric malnutrition. There was no mortality in this series at any time. Conclusions: The OAGB/MGB operation is a safe and effective option for childhood and adolescent patients with severe obesity. There is need for both long-term follow up, prospective, multicentre and larger series studies to confirm the findings in this study.