In many tumors an expression of nm23 gene products is associated with a lower metastatic potential. The aim was to evaluate whether nm23 gene expression in renal cell carcinoma was associated with clinicopathological findings and survival. In 41 patients, the expression of nm23 protein was analyzed in tumor and corresponding kidney cortex tissue by immunohistochemical analysis using a monoclonal nm23-H1 antibody. In all kidney cortex samples intense nm23 staining was found. Of 41 tumors, 15 had high, 12 intermediate, 5 low nm23 expression whereas 9 tumors showed none. There were no differences in nm23 staining between different stages, grades or size of tumor. No correlation between survival and nm23 expression was observed. However, diploid tumors had significantly less nm23 staining compared with aneuploid tumors, indicating that nm23 gene inactivation might be a favorable sign. The expression of nm23 gene products seems not to be correlated to tumor progression and metastatic ability in renal cell carcinoma.