Background: There are insufficient predictive markers for renal cell carcinoma (RCC). Methods: A total of 308 metastatic RCC patients were analyzed retrospectively. Results: The increased hemoglobin (Hb) group had significantly higher progression-free survival and overall survival (OS) compared with the decreased Hb group at 11.5 versus 6.35months (p < .001) and 21.0 versus 11.36months (p < .001) respectively. The 1- and 3-year OS rates were higher in the Hb increased group, i.e., 84% versus 64% and 52% versus 35% respectively. Conclusions: The present study showed that increased Hb levels after tyrosine kinase inhibitor therapy could be a predictive marker of RCC.