Background. The utility of bariatric surgery in type 1 diabetes remains controversial. The aim of the present study is to evaluate glycemic control outcomes in obese patients with type 1 diabetes after bariatric surgery.Methods. A comprehensive search of electronic databases was completed. Inclusion criteria included human adult subjects with BMI ≥35 kg/m²and a confirmed diagnosis of type 1 diabetes who underwent a bariatric surgical procedure.Results. Thirteen primary studies (86 patients) were included. Subjects had a mean age of41.16±6.76years with a mean BMI of42.50±2.65 kg/m². There was a marked reduction in BMI postoperatively at 12 months and at study endpoint to29.55±1.76 kg/m²(P<0.00001) and30.63±2.09 kg/m²(P<0.00001), respectively. Preoperative weighted mean total daily insulin requirement was98±26 IU/d, which decreased significantly to36±15 IU/d (P<0.00001) and42±11 IU/d (P<0.00001) at 12 months and at study endpoint, respectively. An improvement inHbA1cwas also seen from8.46±0.78% preoperatively to7.95±0.55% (P=0.01) and8.13±0.86% (P=0.03) at 12 months and at study endpoint, respectively.Conclusion. Bariatric surgery in patients with type 1 diabetes leads to significant reductions in BMI and improvements in glycemic control.