Objective To investigate the effects of dipeptidyl peptidase 4(DPP-4) inhibitor on serum adiponectin (APN) and high sensitivity C-reactive protein (hs-CRP) in patients with type 2 diabetes mellitus.Methods 45 cases were type 2 diabetes were collected from department of endocrinology,wuxi second People's hospital of jiangsu province from January 2015 to April 2015.45 patients with type 2 diabetes mellitus were randomly divided into treatment group (n=23) and control group (n =22) , treatment group was treated with metformin combined with DPP-4 inhibitor and control group was treated without DPP-4 inhibitor.Before and after treatment,fasting plsma glucose(FPG),postprandial 2h glucose(2hPG),adiponectin, hs-CRP and homeostasis model assessment for insulin resistance(HOMA-IR) were measured.Results Adiponectin was significantly higher in treatment group than before(P<0.05),FPG,2hPG,hs-CRP and HOMA-IR were significantly lower than before(P<0.05).Adiponectin in treatment group was significantly higher than control group post-treatment(P<0.05).2hPG,hs-CRP and HOMA-IR in treatment group were siginificantly lower than control group post-treatment (P<0.05).Conclusion DPP-4 inhibitor could improve insulin resistance in type 2 diabetes mellitus by increasing serum adiponectin and decreasing serum Hs-CRP and HOMA-IR.