The aim of this study was to report our experiences of sleeve gastrectomy (SG) in obese patients with type 1 diabetes mellitus (T1DM) and to assess its metabolic outcomes through a review of the literature and a meta-analysis. We conducted a retrospective review of the electronic medical records of all patients who underwent bariatric surgery between January 2008 and February 2019 at a single institution. A literature search was performed using PubMed, Cochrane library, and Embase, and a meta-analysis for each direct comparison between pre- and postoperative groups was performed using the random effects DerSimonian-Laird method. We identified three obese patients with T1DM who underwent SG. The baseline body mass index (BMI), HbA1c, and total daily insulin dose was 40.8 (37-47.4) kg/m2, 7.1% (6%-7.7%), and 92.3 (54-113) units, respectively. After surgery, the BMI and total daily insulin dose reduced to 32.2 (30.2-37.6) kg/m2 and 22.3 (12-40) units, respectively. However, the HbA1c increased to 7.8% (5.4%-10.8%). In the meta-analysis, the weighted mean reduction in BMI, HbA1c, and total daily insulin dose were 10.69 kg/m2 (95% CI 7.01-14.37, P<0.00001, I2=0%), 0.3% (95% CI -0.10-0.71, P=0.1447, I2=0%), and 58.52 units (95% CI 15.96-101.08, P=0.07, I2=0%), respectively. SG showed excellent weight-reducing effects during a short follow-up period in obese patients with T1DM and improved the glycemic control by reducing insulin requirement.