Objectives This study sought to evaluate the safety and efficacy of rosuvastatin in preventing contrast-induced acute kidney injury (CI-AKI) in patients with diabetes mellitus (DM) and chronic kidney disease (CKD). Background CI-AKI is an important complication after contrast medium injection. While small studies have shown positive results with statin therapy, the role of statin therapy in prevention of CI-AKI remains unknown. Methods We randomized 2,998 patients with type 2 DM and concomitant CKD who were undergoing coronary/peripheral arterial angiography with or without percutaneous intervention to receive rosuvastatin, 10 mg/day (n = 1,498), for 5 days (2 days before, and 3 days after procedure) or standard-of-care (n = 1,500). Patients' renal function was assessed at baseline, 48 h, and 72 h after exposure to contrast medium. The primary endpoint of the study was the development of CI-AKI, which was defined as an increase in serum creatinine concentration ≥0.5 mg/dl (44.2 μmol/l) or 0.25% above baseline at 72 h after exposure to contrast medium. Results Patients randomized to the rosuvastatin group had a significantly lower incidence of CI-AKI than controls (2.3% vs. 3.9%, respectively; p = 0.01). During 30 days' follow-up, the rate of worsening heart failure was significantly lower in the patients treated with rosuvastatin than that in the control group (2.6% vs. 4.3%, respectively; p = 0.02). Conclusions Rosuvastatin significantly reduced the risk of CI-AKI in patients with DM and CKD undergoing arterial contrast medium injection. (Rosuvastatin Prevent Contrast Induced Acute Kidney Injury in Patients With Diabetes TRACK-D; NCT00786136 )