BACKGROUND: Diabetes mellitus (DM) is a major risk factor for contrast-induced acute kidney injury (CI-AKI). DM and CI-AKI result in oxidative damage and inflammation that can be reduced when treated with the coenzyme Q-10 (CoQ10). The aim of this study was to investigate the therapeutic potential of CoQ10 in renal function, renal hemodynamics, oxidative profile and renal histology in diabetic rats subjected to CI-AKI. METHODS: Wistar rats, male, randomized into five groups: citrate: control animals received citrate buffer (streptozotocin vehicle, 0.4 mL); Tween: control animals of CoQ10 treatment received 1% Tween 80 (CoQ10 vehicle, 0.5 mL); DM: animals that received streptozotocin (60 mg/kg); DM + IC: DM animals treated with iodinated contrast (IC, 6 mL/kg); DM + IC + CoQ10: DM animals treated with CoQ10 (10 mg/kg) and that received IC (6 mL/kg). The protocols lasted 4 weeks. An evaluation was made to measure renal function, inulin clearance and serum creatinine, renal hemodynamics by renal blood flow (RBF) and renal vascular resistance (RVR), markers of oxidative stress such as urinary peroxides and nitrate, lipid peroxidation, thiols in renal tissue and renal histological analysis. RESULTS: DM animals showed reduced renal function, which was followed by an increase inserum creatinine and significant reduction of inulin clearance and RBF. It was noticed an increase in RVR and redox imbalance with higher urinary peroxides and nitrate lipid peroxidation levels with depletion of thiols in renal tissue. IC treatment exacerbated these changes in DM + IC. CoQ10 administration ameliorated renal function, prevented hemodynamic changes and neutralized oxidative damage and progression of the histologic damage in the DM + IC + CoQ10 group. CONCLUSION: This study demonstrated the renoprotection properties of CoQ10 in an experimental model of risk factor of DM for CI-AKI. CoQ10 presented an antioxidant effect on the CI-AKI in male diabetic rats by improving renal function and renal hemodynamics, preserving morphology and reducing oxidative stress.