Objective:To examine the characteristics of ultrasonic image in renal tumors for accurate diagnosis of this disease.Methods:Sixty cases with kidney tumor were reviewed concerning the pre-operative confirmation by features of the ultrasonic image.Results:By comparison with the surgical findings and pathological confirmation,57 out of 60(95%)were coincided with the pre-operative ultrasonic localization and 54 in 60(90%)were in agreement with the differential diagnosis by pathological grading.The essential demonstration of malignant kidney tumors were characterized by greater renal artery peak velocity and lower resistance index(RI)as compared with the benign ones(P0.05).Conclusion:The combination of two-dimensional ultrasonic image and color doppler flow imaging(CDFI)can effectively improve the diagnosis of renal tumors.