Mucormycosis is an uncommon infectious complication after renal transplantation and is associated with fatal outcomes. We report 2 cases of transplant renal artery thrombosis and spontaneous rupture caused by mucormycosis. As stenosis, thrombosis, and spontaneous rupture of the transplant renal artery began to occur in both cases after renal transplantation, nephrectomy of the transplanted kidney was performed. Postoperative pathological findings in the transplanted kidney revealed an invasive mucormycosis infection in the renal artery. One patient survived, but the other patient died. This report also presents the diagnosis and treatment processes used for this transplant complication.