Renal stiffness was investigated by using magnetic resonance elastography (MRE) with tomoelastography-postprocessing in 24 participants (12 renal donor-recipient couples) to explore the influence of kidney transplantation on renal viscoelasticity for the first time. Renal stiffness increases immediately after transplantation. These early changes could be due to changes in renal perfusion and increase in renal metabolism, which is also reflected by increase in renal volume. Cold ischemia time was found in being a contributor to changes of solid renal structures. Inccrease in renal stiffness after transplantation could be a novel predictive biomarker for better renal outcome.