Obesity and diabetes mellitus are becoming 2 of the most leading risk factors that threaten public health worldwide. Obesity is a very strong but preventable risk factor for getting type 2 diabetes. Laparoscopic sleeve gastrectomy (LSG) has been a main approach to the surgical management of morbid obesity and type 2 diabetes but its role remains undefined. Here, we overviewed the clinical outcomes and regulatory mechanisms of LSG, aiming at providing thorough theoretical supports and effective technical guidance to the pathogenesis, prognosis, treatment and prevention of type 2 diabetes with obesity. Futher more, the prospectives and main drawbacks (such as considerable heterogeneity and unicity, little comparability and relevance) of LSG are also discussed.