ObjectiveTo systematically review the efficacy and safety of linagliptin in the treatment of type 2 diabetes. MethodsWe searched The Cochrane Library, EMbase, PubMed, CNKI, CBM, VIP and WanFang data to collect randomized controlled trials (RCTs) on linagliptin versus placebo for type 2 diabetes from inception to January 2015. Two reviewers independently screened literature, extracted data and assessed the risk of bias of included studies. Then meta-analysis was performed using RevMan 5.3 software. ResultsA total of 16 RCTs were included. The results of meta-analysis showed:The linagliptin monotherapy group was superior to the placebo group in reducing HbA1c (MD=-0.76, 95%CI -0.85 to -0.66) and FPG (MD=-1.12, 95%CI -1.28 to -0.95), and there were no statistical differences in the incidence of overall adverse events (OR=0.86, 95%CI 0.70 to 1.06) and hypoglycemic (OR=1.19, 95%CI 0.36 to 4.01) between the two groups. The linagliptin combination treatment group (combined with other oral antihyperglycemic drugs) was superior to the placebo combination treatment group in reducing HbA1c (MD=-0.61, 95%CI -0.67 to -0.56) and FPG (MD=-0.79, 95%CI -0.96 to -0.63), and there was no statistical difference in the incidence of overall adverse events between the two groups (OR=1.07, 95%CI 0.92 to 1.24), however, the incidence of hypoglycaemic in the linagliptin combination treatment group was higher than that in the placebo combination treatment group (OR=1.55, 95%CI 1.19 to 2.02). ConclusionLinagliptin is effective and safe in the treatment of type 2 diabetes. Due to the limited quantity and quality of included studies, more high quality studies are needed to verify the above conclusion.