Background: Using long-term (more than 30 years) data from a single center, this retrospective study evaluated changes of independent risk factors affecting renal allograft survival by transplant era. Methods: Of 3,000 cases of kidney transplantation, 2,708 (90.3%), including their follow-up observations, were reviewed. Transplant era was classified according to immunosuppressive regimens as either early group (transplant serial No. 1∼1,500) or recent group (transplant serial No. 1,501∼3,000). Results: There was a significant difference observed in pre-transplant clinical manifestations between the early and recent groups. The number of elderly recipients and donors, number of deceased donors, and cases related to pre-transplant diabetes, pre-emptive transplantation, and retransplantation were differed relative to transplant era. The short- and long-term graft survival rate of the recent group improved significantly, and the effect of human leukocyte antigen mismatching and living donor type disappeared in the recent group. Moreover, pre-emptive transplantation and retransplantation were effective only in the recent group. However, non-immunological factors such as elderly recipients and donors, and immunologic factors such as episodes of acute rejection and types of immunosuppressive regimen were persistent independent risk factors affecting graft survival rate. Conclusions: According to the retrospective survival analysis of a large number of recipients in a single center, risk factors for kidney transplant patients differed by transplant era. However, the independent risk factors associated with elderly recipients and donors (non-immunologic), and episodes of acute rejection, and types of immunosuppressive regimen (immunologic) persisted regardless of transplant era.