Objective To analyze if the increasing the dose and time of vancomycin will increase the renal toxicity risk in patients with resistance to toluene penicillin Staphylococcus aureus (methicillin-resistant Staphylococcus aureus, MRSA) and blood drug concentration significance in the course of treatment.Methods We enrolled 105 patients, mean age (58.0 ±5.8) years;59 males (61.9%) treated in our hospital with MRSA.Patients’ age, sex, serum creatinine (SCr), creatinine clearance rate (CrCl), serum vancomycin concentrations, duration of treatment, acute physiology and chronic health evaluation II score were analysed.The definition of renal toxicity is that SCr is higher than the baseline 0.5 mg/dL, or according to the measurement results of a series SCr:SCr elevation≥50%.The relevant data in patients with renal toxicity and non toxicity were compared.Results 45 (42.9%) had renal toxicity.Vancomycin concentration was significantly higher in renal toxicity patients than non toxicity [(20.9 ±9.8)μg/mL vs. (14.2 ±6.6)μg/mL, P<0.001), serum drug concentration≥15μg/mL (67.8% vs 40.3%; P =0.01) and vancomycin treatment duration (14 days) ( 46.0% vs 21.4%; P =0.011 ) has obvious different scale between two groups. Regression analysis showed that: vancomycin serum concentration≥15μg/mL and prolonged treatment were independent predictors of renal toxicity ( adjusted likelihood ratio =2.83; 95%CI, 1.03 ~7.72, P=0.045).Conclusion The increase of vancomycin dosage and treatment time was the risk of nephrotoxicity.