The surgical procedures, which are performed to patients who are unable to lose weight regardless of the treatments administered and of diets and who have a Body Mass Index (BMI) over 40 or over 35 and suffering from chronic diseases, and therefore, to patients who have serious medical problems, are known as “Bariatric Surgery” or “Obesity Surgery”. With obesity surgery, not only patients may get back to their normal weight, but also the prevalence of diseases related to obesity are reduced; that’s why bariatric surgery plays a crucial role for treatment of obesity. Laparoscopic surgery for obesity shortens the recovery period. The researches on bariatric surgery patients show that patients who have undergone bariatric surgery are less likely to develop the types of cancer linked to obesity when compared to patients who did not undergo bariatric surgery. The reason for this is that while weight loss with dieting and exercise result in 7-10% of weight loss, bariatric surgery ensures 80% of weight loss, if supported by necessary life style changes. In the pre-operative period, eating and drinking habits of patient, diabetes and life style and the status of other health disorders are taken into consideration. Especially, patients between 18 and 60 years of age may undergo this operation. There are several conditions for patients to undergo operation.