Objective To compare contrast-enhanced ultrasound and MRI in the differential diagnosis of breast lesions results. Methods 78 patients with space-occupying lesions were selected in the breast in our hospital from May 2012 to April 2015, they were performed before surgery and MRI results were statistically analyzed to compare the effect of both the differential diagnosis. In which the results of the ultrasound contrast qualitative of contrast-enhanced ultrasound contrast the differences between the indicators. Results (1) qualitative CEUS examination, 40 cases of malignancy in patients with homogeneous enhancement (+) 18 cases, homogeneous enhancement (-) 22 cases, perfusion defect (+) 29 cases, perfusion defect (-) 11 cases, the surrounding Radioactive vessels (+) 26 cases of peripheral vascular radioactivity (-) 14 cases, after strengthening the scope of the lesions increased (+) 24 cases, after strengthening the range of lesions increased (-) 16 cases; homogeneous enhancement in 38 cases of patients with benign (+) 33 cases, homogeneous enhancement (-) 5 cases, perfusion defect (+) 6 cases, perfusion defect (-) 32 cases of peripheral vascular radioactivity (+) 8 cases, peripheral vascular radioactivity (-) 30 cases, strengthening the range of lesions after increase (+) 11 cases, strengthened to increase the range of lesions (-) 27 cases. Uniformity, perfusion defect, whether a neighboring radial artery lesions expand the scope of the differences between benign and malignant breast lesions were statistically significant after strengthening.(2)MRI examination, 39 cases of benign patients, there are 20 cases of progressive type, platform type, 17 cases of type 2 patients clearance; 39 cases of malignant patients, there was one case of a progressive type, platform type there were 14 cases, there were 24 cases of clearance type. It can be seen, the difference between benign and malignant progressive and statistically significant clearance were typed, platform type differences between benign and malignant not statistically significa(3) CEUS diagnosis of four cases of malignant misdiagnosed patients, 4 cases of benign patients were misdiagnosed. MRI diagnosis in three cases of malignant were misdiagnosed patients, three cases of benign patients were misdiagnosed. The effect of ultrasound diagnostic imaging and MRI are not statistically significant. Conclusion Ultrasound imaging and breast MRI lesions in the differential diagnosis effect with good consistency, all have very good value in clinical diagnosis.