Background: The purpose of this study was to investigate the effects of preoperative statin therapy (PST) on short-and long-term renal dysfunction after cardiac surgery. Methods: We searched for reports that investigated the effects of PST on renal outcomes after cardiac surgery in the electronic literature databases PubMed, Ovid, and Elsevier. Results: Twenty-six reports including 59,771 patients were selected for meta-analysis. The meta-analysis revealed that PST significantly reduced the incidence of postoperative renal dysfunction (odds ratio [OR], 0.89; 95% confidence interval [CI], 0.84-0.95; P < 0.0001) without significant heterogeneity (I-2 = 28.1%; P = 0.093). PST also significantly reduced the need for postoperative renal replacement therapy (OR = 0.76; 95% CI, 0.62-0.92; z = 2.77; P = 0.006); particularly in the subgroup of patients who underwent isolated coronary artery bypass grafting, the rate of renal replacement therapy was reduced by 56% (OR, 0.44; 95% CI, 0.30-0.66; z = 4.08; P < 0.0001) with low heterogeneity (I-2 = 18.7%; P = 0.297). Meta-analysis for the outcome of acute kidney injury (AKI) revealed that PST reduced the incidence of postoperative AKI by 13% (OR, 0.87; 95% CI, 0.80-0.94; P = 0.001) and 7% (OR, 0.93; 95% CI, 0.86-0.99; P = 0.031), respectively, for subgroups of patients whose AKI was evaluated using the Acute Kidney Injury Network (AKIN) or the Risk, Injury, Failure, Loss, and End Stage (RIFLE) criteria, without significant heterogeneity for either. Conclusions: PST might be a promising therapy to reduce renal complications after cardiac surgery although large-scaled randomized controlled trials are needed to further verify the conclusion.