Objective To investigate the contrast-enhanced ultrasound in breast malignant tumors.Methods The retrospective analysis of data of two cases of rare malignant breast tumor ultrasound and pathology analysis and summary.Results Contrast enhanced ultrasound of breast malignant tumors showed lesions early fast inhomogeneous enhanced with partial perfusion defect region or network like high enhancement, peripheral enhancement after contrast focus and radial length/width ratio decrease, but Benign tumors showed enhanced lesions early slowly and uniformly weak enhancement and there were no peripheral radial reinforced.Conclusion Contrast enhanced ultrasound can be dynamic observation of breast lesions and peripheral microvascular perfusion condition, help to improve the differential diagnosis of benign and malignant breast lesions.