To determine the incidence and determinants of delayed graft function due to post-transplant acute tubular necrosis in live related donor renal transplantation. This is a retrospective study of 337 recipients of live related donor renal graft performed between1986 and 2006. Of these recipients, 24 (7.1%) subjects developed delayed graft function with no evidence of acute rejection, cyclosporin toxicity, vascular catastrophe or obstructive cause and had evidence of acute tubular necrosis (ATN Group). These subjects were compared with recipients (n= 313, 92.9%) who had no clinical or biochemical evidence of ATN. Mean age, and gender distribution of recipients was similar in the two groups (ATN group 35.7 ± 8.3, non-ATN group 34.3 ± 7.5, P= 0.43). Gender distribution of the recipients (men 279, 89.1% vs. 21, 87.5%, P= 0.80) as well as donors (women 221, 70.6% vs. 18, 75.0%, P= 0.75) was also similar. In ATN group as compared with non-ATN group the donor age was significantly greater (56.6 ± 8.3 vs. 46.6 ± 11.2 years, P