Objective: To determine the prognostic value of the American Society of Anesthesiologists (ASA) classification and of the main clinical pathologic variables in renal cell carcinoma (RCC) patients who underwent surgical treatment. Methods: In this international collaborative study, 376 RCC patients who underwent partial nephrectomy (PN) or radical nephrectomy (RN) during the period 1989-2009 were assessed. The pathological data were reviewed by a single pathologist, and all of the surgically treated patients had been previously evaluated by a team of anesthesiologists and classified as ASA 1, ASA 2, or ASA 3. Results: In total, 318 patients were included in the study, with a mean followup of 48 months. Incidental tumors represented 47% of the cases, while 11.6% presented with metastases at diagnosis. Among the patients assessed, 38 (11.9%) were classified as ASA 1, 213 (67%) as ASA 2, and 67 (21.1%) as ASA 3. An association between the ASA classification and the main clinicopathological variables of RCC was observed. The univariate analysis for overall survival (OS) revealed significant differences in the survival curves according to the ASA classification (p < 0.001). High-grade neoplasms, the presence of metastasis at diagnosis, clinical stage III/IV, and incidental tumors remained as independent predictors of survival. Moreover, the multivariate analysis revealed a negative impact of the ASA classification on OS (p = 0.001). Conclusions: The present study demonstrated a correlation between the ASA classification and the main prognostic factors of RCC and its impact on survival rates. ASA 3 patients had more aggressive tumors, increased risk of perioperative complications, and worse outcomes compared with ASA1 or ASA 2. Thus, the ASA classification may be considered an additional tool for assessing and planning the treatment of RCC patients.