The prevalence of end-stage renal disease (ESRD) in patients with diabetes mellitus (DM) has increased. Despite the higher prevalence of some diseases in diabetic ESRD patients, compared with non-diabetic subjects, few studies have focused on difference in pattern of hospital admissions after kidney transplantation in these groups. This study compares the causes of re-hospitalization after renal transplantation in ESRD attributable to DM and non- diabetes mellitus (NDM) patients. We performed a retrospective study on 366 re-hospitalization records in Baqyiatallah hospital, Tehran, Iran from 1994 to 2006. Of these, 69 were due to DM patients and 297 were due to NDM patients. Causes of admission were categorized to renal dysfunction, infection, surgical complication, and macrovascular disease and were compared in two groups. The proportion of infections (59.4% vs 43.1%, p<0.05) and surgical complications (14.5% vs 5.7%, p<0.05) were higher in diabetics compared to non-diabetics. No significant differences were found in the proportion of macrovascular disease (0% vs 3%, p>0.05) or renal dysfnction (34.8% vs 44.4%, p>0.05). According to the results of this study, diabetic renal transplant patients are at higher risk of infections and surgical complications following renal transplant. This recommends a closer follow-up of diabetics after kidney transplantation, which may be beneficial in decreasing rate of preventable hospitalizations.