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INTRODUCTION Herein, we discuss clinicopathological analyses of cases of chronic renal allograft arteriopathy (CRA) after renal transplantation and clarify the mechanisms underlying the development and prognostic significance of CRA. METHODS CRA was diagnosed in 34 renal allograft biopsy specimens (BS) obtained from 27 renal transplant patients who were followed up at the Department of Urology and Transplant Surgery, Toda Chuo General Hospital, between January 2010 and December 2020. RESULTS CRA was diagnosed at a median 33.4 months post-transplantation. Of the 27 patients, 16 had a history of rejection. Among the 34 BS showing evidence of CRA, the CRA was mild (cv1 in Banff's classification) in 22, moderate (cv2) in 7, and severe (cv3) in 5 patients. We then classified the 34 BS showing evidence of CRA based on their overall histopathological features as follows: cv alone seen in 11 (32%) BS, cv + antibody-mediated rejection (AMR) in 12 (35%), and cv + T-cell-mediated rejection (TCMR) in 8 (24%). Loss of the renal allograft occurred during the observation period in three patients (11%). Of the remaining patients with functioning grafts, deterioration of renal allograft function after biopsies occurred in seven cases (26%). CONCLUSIONS Our study results suggest that AMR contributes to CRA in 30%-40% of cases, TCMR in 20%-30% of cases, isolated v lesions in 15% of cases, and cv lesions alone in 30%. The intimal arteritis was a prognostic factor in CRA.