Background: Fibrosis progression is a major prognosis factor in kidney transplantation. Its assessment requires an allograft biopsy, which remains an invasive procedure at risk of complications. Methods: We assessed renal stiffness by magnetic resonance elastography (MRE) as a surrogate marker of fibrosis in a prospective cohort of kidney transplant recipients, as compared to the histological gold standard. Interstitial fibrosis was evaluated by three methods: the semi-quantitative Banff ci score, a visual quantitative evaluation by a pathologist and a computer-assisted quantitative evaluation. MRE-derived stiffness was assessed at the superior, median and inferior poles of the allograft. Results: We initially enrolled 73 patients, but only 55 had measurements of their allograft stiffness by MRE prior to an allograft biopsy. There was no significant correlation between MRE-derived stiffness at biopsy site and the ci score (rho=-0.25, p=0.06) or with the two quantitative assessments (pathologist, rho=-0.25, p=0.07, computer-assisted, rho=-0.21, p=0.12). We observed negative correlations between the stiffness of both biopsy site and whole allograft, with either the glomerulosclerosis percentage (rho=-0.32, p=0.02 and rho=-0.31, p=0.02, respectively) and the overall nephron fibrosis percentage, defined as the mean of the percentages of glomerulosclerosis and interstitial fibrosis (rho=-0.30, p=0.02 and rho=-0.28, p=0.04, respectively). At patient level, mean MRE-derived stiffness was similar across the three poles of the allograft (± 0.25 kPa). However, a high variability of mean stiffness was found between patients, suggesting a strong influence of confounding factors. Finally, no significant correlation was found between mean MRE-derived stiffness and the slope of eGFR (p=0.08). Conclusions: MRE-derived stiffness does not directly reflect the extent of fibrosis in kidney transplantation.