Objective To compare the short-term effect of bariatric surgery on obesity patients with type 2 diabetes mellitus between laparoscopic Roux-en Y gastric bypass (LRYGB) and laparoscopic sleeve gastrectomy (LSG). Methods A retrospective study was performed from January 2011 to December 2018 for the obesity patients with type-2 diabetes who underwent LRYGB (n=38) and LSG (n=38) and matched in age, gender, body mass index, glycosylated hemoglobin A1c level, and diabetes duration to analyze the surgical effects. Results There was no any major complication and no any malnutrition during 24 months of follow-up. Both surgical procedures achieved weight loss and diabetes remission significantly. LRYGB reduced serum cholesterol levels (4.31±0.94) mmol/L vs. (5.36±1.22) mmol/L, P<0.01 and low-density lipoprotein-c levels (2.39±0.70) mmol/L vs. (3.22±0.94) mmol/L, P<0.01, as well as diabetes remission rate by glycosylated hemoglobin A1c (89.5% vs. 71.1%, P=0.044) significantly when compared with LSG. Conclusions Both