– OBJECTIVE: In this study, we aimed to investigate the relation between the mRNA expression levels of VHL, TIMP-3 and RASSF1A genes, and the histopathological and clinical characteristics of patients with renal tumors. PATIENTS AND METHODS: Radical nephrectomy specimens of cases presented without neoadjuvant treatment were confirmed to be cancerous, non-cancerous, benign, and healthy after removal from separate localizations. A total of 69 patients with kidney tumors (138 tissue samples) were included in the study group. RNA isolation, reverse transcriptase PCR (RT-PCR), and quantitative real time PCR (qPCR) were performed, and the GAPDH gene was used to normalize mRNA levels. RESULTS: In the RCC cancerous tissue, TIMP-3 levels increased 1.3 times and RASSF1A levels increased 1.4 times compared to the corresponding levels in non-cancerous tissues, and there was no statistically significant difference in these values. On the other hand, VHL gene expression levels in cancerous tissue were 2.8 times higher than in matched adjacent noncancerous tissues (p < 0.05). In the case of oncocytomas, TIMP-3 levels were found to be 3.2 times higher, RASSF1A levels 3.8 times higher, and VHL levels 2.2 times lower than the corresponding levels in healthy tissues (p < 0.05). CONCLUSIONS: The roles of VHL, TIMP-3, and RASSF1A mRNA expression in contributing to the development of renal tumors could not be clearly established. Further studies are therefore required to elucidate the mechanisms underlying renal tumors.