Objective：To evaluate the function of contrast-enhanced ultrasound in differential diagnosis of benign and malignant breast Lesions. Methods：Firstly,172 patients were performed by color Doppler ultrasound to observe the size、shape、internal echo and blood perfusion of the lesions.Secondly,all patients were checked by contrast-enhancement ultrasound,viewed the Imaging features between the benign and malignant breast Lesions.Compared the results of the benign and malignant breastlesions by contrast—enhanced ultrasonography with the result of the pathology. Result:84 cases of malignant breast Lesions were confirmed by CEUS, the other 88 was benign breast Lesions,thus,83 cases of malignant breastlesions were confirmed by pathology, the other 89 was benign breastlesions. the Enhanced Mode，distribution patterns，enhanced intensity boundary conditions and lesion enlarged after CEUS were statistically significant between benign and malignant breastlesions(p＜0.001). Conclusion:It has important value for the diagnosis of benign and malignant lesions by useing the characteristics of contrast-enhancement ultrasound.