0 55). The Vmax and Vmin of the patients were singnificantly higher than those of healthy people. The RI of healthy subjects was higher than that of the patients. The Vmax and Vmin of the kidney with tumor was singnificantly higher than that of the other normal kidney side. Conclusion The hemodynamic features of the kidney tumors and kidney artery were valuable to the differential diagnosis of the malignant and benign kidney tumors.