Objective: To assess the potential significance of proliferating cell nuclear antigen (PCNA) labelling indexes (PCNA-LI) and AgNORs number in evaluation of proliferative activity of Wilms′ tumor. Methods: A silver staining for AgNORs and an immunohistochemical method PCNA staining were performed on the biopsy specimens taken from 34 children with Wilms′ tumor. Results: No significant differences were observed between PCNA-LI and the pathological types and clinical stages, whereas fraction of S-phase and PI and the number of AgNORs were significantly higher in patients with PCNA-LI≥25% than that in patients with PCNA-LI<25%. The number of AgNORs/cell correlated well with both pathological types and clinical stages. The combination of PCNA-LI and AgNORs can accurately reflect the proliferative activity of cancer cells in Wilms′ tumor. Conclusion: The current pathological types and clinical stages may reflect the aggressive activity in Wilms′ tumor, but insufficient. The simultaneous determination of PCNA-LI and AgNORs count could be used as the essential complementarity of conventional pathological types and stages for accurate evaluation of biologic behaviour of Wilms′ tumor.