CA 15-3, CA 125 and β -2 microglobulin are three common tumor markers currently used for diagnosis, prognosis, assessment of therapeutic response, and/or to evaluate recurrence in breast and ovarian cancer and malignant lymphoproliferative disorders, respectively. In the present prospective study we assessed the role of these three serum proteins as biomarkers for renal cell carcinoma (RCC), as well as any association between tumor marker levels and clinical-pathological parameters. CA 15-3, CA 125, and β -2 microglobulin were preoperatively measured in 332 patients who underwent nephrectomy for RCC. Estimates of cancer-specific survival (CSS) was calculated according to the Kaplan-Meier method. Multivariate analysis was performed to identify the most significant variables for predicting CSS. Preoperatively, 35.2% (n = 117), 9.6% (n = 32) and 30.4% (n = 101) of the patients had abnormal levels of CA 15-3, CA 125 and β -2 microglobulin, respectively. Statistically significant differences resulted between CA 15-3, CA 125 and β -2 microglobulin values and tumor size, Fuhrman grade, presence of lymph node, and visceral metastases. CSS was significantly decreased for patients with high levels of CA 15-3, CA 125, and β -2 microglobulin (P < 0.0001, P < 0.0001, and P = 0.001, resp.). At multivariate analysis only age, the presence of visceral metastases, and high levels of CA 15-3 were independent adverse prognostic factors for CSS.