Delayed graft function (DGF) is a common problem in kidney transplantation and is associated with adverse graft outcomes and increased cost of care. The purpose of this study was to determine if the duration of dialysis increases the risk of DGF. All primary deceased donor renal transplants between January 2000 and December 2003 were identified in the Organ Procurement and Transplant Network database. Two separate definitions of DGF were used: dialysis in the first week post-transplant (DPT) and creatinine drop of < 25% in the first 24 h or slow graft function (SGF). The rate of DPT and SGF increased from 5.7% and 34.4%, respectively, for pre-emptively transplanted patients, to 32% and 49.9% for patients who had been on dialysis for 6 or more years. When compared to pre-emptive transplantation, increasing duration of dialysis increased the adjusted risk of both DPT and SGF (OR 6.64 (95% CI 5.49-8.03) and OR 1.76 (95% CI 1.56-2.00) for patients on dialysis for 6 or more years, for DPT and SGF, respectively. A strong association between duration of dialysis and DGF exists, and investigations into the mechanisms by which dialysis influences DGF may lead to useful interventions to limit this complication.