Renal cell carcinoma frequently extends into the vena cava and occasionally, even into the right atrium. We experienced 2 cases of renal cell carcinoma extending into the inferior vena cava by radical nephrectomy and complete removal of thrombi in the cava by joint approach with urologic surgeons. In the literature, improvement of survival by complete removal of tumor thrombi in the vena cava was documented and joint approach of cardiovascular surgeons and urologic surgeons result in appropriate surgical approach.