Suitable selection of donors is key to the success of human islet isolation and transplantation. Although several important donor-related factors have been identified previously, they needed to be confirmed in our setting. The aims of this study were: (1) to compare the characteristics of islet donors with those of pancreas donors (national transplant registry). (2) to compare the characteristics of islet donors resulting in a successful isolation in our facility with the characteristics of pancreas donors, and (3) to compare the characteristics of islet donors at this facility, whether or not isolation was successful, with donors elsewhere whose islets were transplanted and included in the Collaborative Islet Transplant Registry. The 35 islet isolations completed at our facility were analyzed for various characteristics. Significant differences were seen in donor age body mass index (BMI), and body weight between our islet donors and our pancreas donors (P < .001). These differences were maintained in the subgroup analysis corresponding to donors of successful isolations compared to pancreas donors (P < .01). Most successful isolations in our islet isolation facility were associated with donors of BMI >25. The percentage of successful isolation (>300,000 IEq) was higher among donors with a body weight >90 kg. We concluded that there was little overlap between the donor profiles for pancreas transplantation and for islet transplantation. More specific selection criteria relative to both BMI and body weight for islet donors may result in greater success of pancreas islet isolation and transplantation.