Objective：This study aimed to evaluate the prognostic value of the renal chronicity score in patients with diabetic kidney disease（DKD）and compare it with the traditional DKD Research Committee of the Renal Pathology Society（RPS）pathological classification. Methods：Clinical and pathological data from 129 patients diagnosed with DKD through renal biopsy at the First Affiliated Hospital of Nanjing Medical University between January 2014 and September 2020 were retrospectively analyzed. Based on the renal chronicity score，patients were categorized into three groups：minimal（n=34），mild（n=50），and moderate-severe（n=45）. The clinical characteristics and pathological indicators of each group were compared，and these results were evaluated against the DKD RPS pathological classification. The Cox regression analysis was used to identify factors influencing poor renal outcomes. The Kaplan Meier survival curves were employed to compare cumulative renal event -free survival rates，and the receiver operating characteristic （ROC）curve analysis was performed to assess the diagnostic value of the renal chronicity score，both alone and in combination with estimated glomerular filtration rate（eGFR）and 24-hour urinary protein to predict renal outcomes. Results：Patients with higher renal chronicity scores exhibited more severe renal dysfunction，greater anemia，and higher pathological grades according to the DKD RPS pathological classification. The Kaplan - Meier’s survival analysis showed that patients with higher renal chronicity scores had significantly lower cumulative survival rates without renal endpoint events，indicating poorer prognosis（P ＜ 0.05）. The Cox regression analysis identified a higher renal chronicity score as an independent risk factor for renal endpoint events（P ＜ 0.05）. The ROC curve analysis demonstrated that the diagnostic value of the renal chronicity score was slightly lower than that of the DKD RPS pathological classification（area under the curve，AUC=0.651 vs. 0.875），although no statistically significant difference was found between the two methods. When combined with eGFR and 24 - hour urinary protein，the AUC for the renal chronicity score increased to 0.810. Conclusion：Higher renal chronicity scores in patients with DKD are associated with more severe renal impairment and serve as independent risk factors for poor renal prognosis. Combining the renal chronicity score with clinical indicators，such as eGFR and 24- hour urinary protein，significantly enhances the accuracy of prognostic assessment