Objective: To explore the value of full-angle ultrasonic shear wave elastography in differentiating benign and malignant breast diseases. Methods: After constructing a new ultrasonic shear wave elastography system, the clinical and ultrasonographic data of 74 patients with mass breast diseases were retrospectively analyzed. The patients were divided into benign group and malignant group according to the pathologic results. Meanwhile, the significant indicators of difference were screened out for ROC analysis, and the curve characteristics were compared. Results: Eratio-45°, Eratio-225°, Emax-90°, Emax-270°, Emean-0° and Emean-180° were significantly different between the benign and malignant groups. The AUC of ROC were 0.71, 0.81, 0.83, 0.80, 0.86 and 0.83, respectively. The results of model evaluation showed that the specificity of model-Eratio-45° was relatively low (0.42), while the other 5 indicators showed high specificity (0.73-0.78). Conclusions The full-angle ultrasonic shear wave elastography can provide more information for differentiating benign from malignant breast diseases.