BACKGROUND : The purpose of this study was to compare insulin degludec with insulin glargine in terms of efficacy and safety in patients with type 2 diabetes. METHODS : We systematically searched PubMed, Embase, Web of Science, and Cochrane Library databases for randomized controlled trials published prior to 13 August 2018 (no language restrictions) which compared insulin degludec with insulin glargine. Our main endpoints were glycemic control, hypoglycemic event, weight gain, and serious adverse events (SAEs). We assessed pooled data using random-effects models. RESULTS : A total of 15 studies that included 9619 patients in the insulin degludec arm of the studies and 7075 patients in the insulin glargine arm were identified and subsequently assessed. Our analysis showed that compared with insulin glargine, insulin degludec yielded an improved mean reduction in fasting plasma glucose (FPG) (weighted mean difference [WMD] - 5.20 mg/dL, 95% confidence interval [CI] - 7.34, - 3.07, P < 0.00001) and a lower ratio of participants experiencing ≥ 1 severe hypoglycemic event (relative risk [RR] 0.68, 95% CI 0.50, 0.93, P = 0.01) and nocturnal hypoglycemia (RR 0.81, 95% CI 0.75, 0.88, P < 0.0001); however, in the insulin degludec group there was a lower ratio of participants with glycated hemoglobin (HbA1c) of ≤ 7.0% (RR 0.92, 95% CI 0.86, 0.98, P = 0.01). There was no statistically significant difference between the two treatment groups for HbA1c reduction (WMD 0.03, 95% CI - 0.00, 0.07, P = 0.08), body weight gain (WMD 0.12, 95% CI - 0.19, 0.43, P = 0.46), and proportion of participants with SAEs (RR 0.97, 95% CI 0.92, 1.02, P = 0.20). CONCLUSIONS : Insulin degludec and insulin glargine provide similar glycemic control, but insulin degludec also lowers the risk of hypoglycemia. Consequently, insulin degludec may be an alternative treatment for the management of patients with type 2 diabetes who are prone to hypoglycemia with insulin glargine.