Renal cell carcinoma tends to progress into the renal vein and inferior vena cava. We investigated 14 cases of renal cell carcinoma with tumor thrombus in the inferior vena cava. Surgery was performed in nine cases and mean survival was 53 months. Two cases are alive 8 years after the operation without recurrence or metastasis. The mean survival of 5 cases without operation was 7 months. Surgical management should be considered as a benefit for RCC patients with tumor thrombus in the inferior vena cava.