Obesity is one of the major health challenges throughout the world. The association between obesity and diabetes is well established because 90% of patients with type 2 diabetes mellitus (T2DM) show excess body weight. The aim of the study was to evaluate the effect of laparoscopic sleeve gastrectomy (LSG) on morbid obesity and type 2 diabetes (T2DM) in the long-term follow-up. One hundred ninety-five obese patients, 78 with T2DM, were evaluated before and after LSG up to 10 years, to identify complete diabetes remission (FPG 5 years) follow-up respectively. Furthermore, 45.2% maintained complete remission for at least 5 years and about 36% showed a persistent but improved diabetes. None of the patients cured from diabetes had a duration disease greater than 8 years and a glycemic control requiring insulin. The prevalence of hypertension and dyslipidemia significantly decreased from 49 to 35% and from 51 to 40% respectively. LSG significantly improves body weight, diabetes, hypertension, and dyslipidemia in long-term follow-up.