OBJECTIVE:To observe the clinical efficacy of sitagliptin combined with benazepril in the treatment of diabetic nephropathy(DN). METHODS:Sixty DN patients admitted to our hospital during Sept. 2014-Jun. 2015 were divided into sitagliptin group,benazepril group,drug combination group according to random number table,with 20 cases in each group. Based on routine treatment,sitagliptin group was given sitagliptin 100 mg orally,qd;benazepril group was given Benazepril 10 mg orally,qd;drug combination group was given sitagliptin 100 mg+benazepril 10 mg orally,qd. The drug dosage would be doubled if the blood pressure of patients in 3 groups had not yet reached the standard. Treatment course of 3 groups lasted for 12 weeks. The levels of 24 h urine protein,IL-6 and Cys-C were measured in 3 groups before and after treatment. Clinical efficacies and the occurrence of ADR were observed. RESULTS:Total response rate of drug combination group(90.00%)was significantly higher than those of sitagliptin group (65.00%)and benazepril group(70.00%);there was statistically significance(P<0.05). After treatment,the levels of 24 h urine protein,IL-6 and Cys-C in 3 groups were significantly lowered,compared to before treatment;those of drug combination group was significantly lower than those of other 2 groups;there was statistically significance(P<0.05). There was no statistical significance in above indexes between sitagliptin group and benazepril group(P>0.05). No obvious ADR was found in 3 groups during treatment. CONCLUSIONS:Both sitagliptin and benazepril can decrease the levels of 24 h urine protein,IL-6 and Cys-C,while drug combination shows better effect and clinical response rate,and does not influence the safety of drug use.