OBJECTIVES: Evaluate the results on the efficacy and safety of bariatric surgery vs. medical treatment in remission of type 2 diabetes mellitus (T2DM) and control of blood glucose levels in patients with Body Mass Index ≥ 30. METHODS: Following the methodological guidelines for the development of PTC Ministry of Health, was first drafted the guiding question of the study through the PICO, then a search was conducted in the main databases (PubMed, Embase, Cochrane, Lilacs and CRD). Each study recovered in the databases was selected and evaluated by two independent researchers, their inconsistencies resolved by consensus, when there was no consensus, the assessment of a third investigator was requested. RESULTS: Bariatric surgery showed to be effective and safe in reducing glycated hemoglobin levels, fasting blood glucose levels as well as the augmenting the chances of remission of type II diabetes in obese patients. CONCLUSIONS: However, the variability in the magnitude of the results indicated the need for new data from the 18 ongoing clinical trials. In other words, the technology "bariatric surgery" is efficacious as a whole, but there is a high variability in the treatment effect, depending of surgical technique.