Objective To investigate the effect of CEUS on the optimal reevaluation of BI-RADS 4 breast masses.Methods 174 patients with 180 breast masses were screened as BI-RADS type 4 or above by conventional ultrasound evaluation. Their classification was re-evaluated and adjusted based on the feature analysis of CEUS， and compared with pathological results. The subject operating characteristic (ROC) curve was used to evaluate the risk reassessment value of CEUS for breast masses above BI-RADS 4.Results Among 180 breast masses， 99 were malignant and 81 were benign. The sensitivity， specificity， accuracy， positive predictive value and negative predictive value of BI-RADS classification for malignant tumor diagnosis before adjustment were 90.91%， 80.25%， 86.11%， 84.91% and 87.84%， respectively. The sensitivity， specificity， accuracy， positive predictive value and negative predictive value of BI-RADS classification adjusted by CEUS in the diagnosis of malignant masses were 94.95%， 81.48%， 88.89%， 86.24% and 92.96%， respectively. The area under the ROC curve of BI-RADS classification after adjustment was 0.947， which was better than 0.900 before adjustment (P<0.05).Conclusion Combined with CEUS， it plays a certain role in optimizing and reevaluating the classification of conventional ultrasound BI-RADS， further clarifying the nature， avoiding missed diagnosis and reducing unnecessary biopsies， which will improve the diagnostic confidence of ultrasound doctors in breast masses to a certain extent.