It is the most common abatement obesity surgery in the world. The stomach volume is reduced and the absorption is restricted. The weight loss rates obtained between Mini-gastric bypass and Roux-y gastric bypass are almost the same. The stomach is first formed approximately 30-40 cc pouch from the junction with the esophagus. The small intestine is then cut into approximately 50-70 cm from the first part. The incised part is anastomosed to the newly created stomach pad. On the other side, 150 cm from the anastomosis is counted and connected to the other cutter. This method provides 70-80% loss of excess weight. The effect on diabetes is around 80%. Mineral and vitamin supplements are necessary because absorption is limited.