Interleukin‐17 (IL‐17) plays an important role in the regulation of cellular and humoral immune responses. Recent studies suggest a role for IL‐17 in transplantation. Our study investigated whether quantifying IL‐17+ cells in renal transplant biopsies during acute rejection could have additional prognostic value for better stratifying patients at risk for nonresponsiveness to anti‐rejection therapy and future graft dysfunction. Forty‐nine renal biopsies with acute rejection were double immunostained and quantitatively analyzed for IL‐17 and CD3 (IL‐17+ T‐lymphocytes), tryptase (IL‐17+ mast cells) or CD15 (IL‐17+ neutrophils). Total IL‐17+ cell count correlated with total percentage of inflamed biopsy and estimated GFR during rejection. Most IL‐17+ cells were mast cells and neutrophils. We could hardly find any IL‐17+ T‐lymphocytes. IL‐17+ mast cells correlated with interstitial fibrosis/tubular atrophy (IF/TA). None of the IL‐17+ cell counts had an additional prognostic value for response to anti‐rejection treatment. Multivariate analysis correcting for C4d positivity and time from transplantation to biopsy showed that total IL‐17+ cell count independently predicts graft dysfunction at the last follow‐up, which was validated in an independent cohort of 48 renal biopsies with acute rejection. We conclude that intragraft IL‐17+ cell count during acute allograft rejection could have an additional value for predicting late graft dysfunction.