Objective:To evaluate the value of color doppler sonography in the diagnosis and preoperative assistive positioning of primary hyerparathyroidism. Methods:We retrospectively analyzed the ultrasonographic results of 46 cases,who received surgical operations from 1998.8 to 2009.4. Results:Of all 46 patients,43 lesions were detected in 41 patients. The detection rate was 89.1% (41/46). Those lesions manifested as solitary,well demarcated,round or oval hypoechoic masses. The masses located posterior to the inferior thyroid vessels. In color doppler image,lesions were hypervascular. Arterial and venous flow parttern were detected by spectrum doppler. All the lesions dected by ultrasonography were testified by operation,and the accuracy of preoperation positioning was 100%. Conclusion:Color dopper ultrasonography is an effective method in the diagnosis of primary hyperparathyriodism and can be an optimal choice for the preoperative positioning.