Background: Hyperuricemic patients have been predisposed to cardiovascular disease, hypertension, and RENAL disease. Hyperuricemia is implicated in endothelial dysfunction and in increased production of inflammatory mediators including C-reactive protein.Objective: To evaluate the prevalence of hyperuricemia and its risk factors among RENAL transplant recipients.Methods: A retrospective observational study was conducted among 4217 RENAL transplant recipients between April 2008 and January 2011. All patients referred from different kidney transplant centers, Tehran, Iran to a single laboratory. The mean±SD age of TRANSPLANTATION was 5±4 (median: 4.2) year. During this period, uric acid was measured in 17, 686 blood samples of 4217 RENAL transplant recipients (64% male and 36% female). Hyperuricemia was defined as a serum uric acid (SUA) level ³7.0 mg/dL in males and ³6.0 mg/dL in females that persisted for at least two consecutive tests performed. Moderate to severe hyperuricemia was also defined as a SUA level ³8.0 mg/dL. Multivariate regression analysis was used for identifying risk factors for hyperuricemia.Results: The median age of recipients was 38 years. The majority of cases were male (63%). The median age of the donor was 28 years. The majority of grafts came from living donors (84.6% unrelated and 7.8% related), whereas 7.6% of patients received a deceased donor graft. We found that 1340 (31.8%) of recipients had hyperuricemia. Moderate to severe hyperuricemia was observed in 572 (13.6%) of patients. Although hyperuricemia was frequently occurred in women (34% in women vs 25% in men, p<0.001), the rate of moderate to severe hyperuricemia was higher in men compared to women (15.5% vs 10.3%, p<0.001). There was a significant relationship between SUA and serum creatinine (p<0.001) as well as cyclosporine levels (p<0.001). In multivariate logistic regression, we found that, the increased trough level of cyclosporine was a risk factor of hyperuricemia.Conclusion: Since hyperuricemia is frequently seen in RENAL transplant recipients and high level of cyclosporine is the most important risk factor for developing hyperuricemia, the effective treatment would be cyclosporine dose reduction as much as possible.