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Background&Objective: There are different methods including H&E, imonhistochemstry, flu cytometry, AgNOR staining for differentiation reactive hyperplasia from lymphoma. This study was done to determine diagnostic validity of AgNOR staining for differentating non-Hodgkin lymphoma from reactive hyperpalsia. Materials&Methods: Fifty parafin blocks belong to patients with confirmed diagnosis are as below: Thirty five block with lymphoma and fifteen blocks with reactive hyperplasia. AgNor dots among one hundred cells were counted, by two experienced pathologists. The mean of AgNOR dots were calculated. Student T-test used to campare mean AgNOR dots. Results: The mean AgNOR count was 2.2 (range 1.4-3, SD=0.8) in reactive hyperplasia and 6.7 (range 3.9-9.5, SD=2.8) in non-Hodgkin lymphoma. A statistically significant difference was observed between the AgNOR count of reactive hypeerplasia and non-Hodgkin lymphoma (p<0.05). Conclusion: The findings support the validity of AgNOR technique for differentiating and confirming non-Hodgkin lymphoma from reactive hyperplasia.