De novo renal cell carcinoma (RCC) rarely occurs in kidney allografts; however, the risk of RCC in these patients is 100-fold that of the general healthy population. Although total nephrectomy has been the standard treatment for kidney allograft RCC, several authors have reported that early-stage RCC in kidney allografts was successfully treated with nephron-sparing surgery. We herein describe a new procedure involving renal autotransplantation and extracorporeal nephron-sparing surgery, which was performed to treat de novo RCC near the hilum of a transplanted kidney. In the 22 months since transplantation, the patient's renal function has been favorable, and no recurrence has been observed. In conclusion, renal autotransplantation is a feasible technique for the treatment of RCC in kidney allografts, especially RCC located near the hilum.