ObjectiveTo explore the effect of gastric bypass (GBP) on metabolic syndrome (MS) and the related mechanisms. MethodsThe literatures addressed the effect of GBP on glucose metabolism and blood pressure were retrospectively analyzed. ResultsIt showed that GBP achieved durable level of blood glucose, remission of dylipidemia and hypertension, however, which occurred before significant weight loss. The changes of many factors such as food intake, gastrointestinal hormones, adipocytokines, fat distribution might be involved in GBP to improve MS. ConclusionGBP seems to achieve the control of MS as a primary and independent effect, rather than secondary to the treatment of overweight.