Objective To analyze the efficacy of quantitative parameters of shear wave elastography (SWE) in differentiating benign from malignant breast masses and their correlations with biological parameters.Methods A total of 100 patients with suspected breast cancer examined in the Department of Ultrasound of Affiliated Hospital of Gansu University of Chinese Medicine from September 2018 to October 2021 were selected. All of them underwent SWE, and they were divided into malignant group and benign group based on the pathological results obtained by the surgery or puncture examination. The quantitative parameters of SWE were compared between the two groups, and the value of SWE quantitative parameters in predicting the malignancy of breast masses was analyzed by receiver operating characteristic (ROC) curve. All the masses were investigated with immunohistochemical assays, and SWE quantitative parameters were compared among breast masses with different biological characteristics. In addition, the correlation between SWE quantitative parameters and biological parameters of breast masses were analyzed via Kendall rank correlation test.Results AE-max, Shell1 E_max, Shell2 E_max and Shell3 E_max in the malignant group were higher than those in the benign group (P < 0.05). The ROC curve analysis exhibited that the area under the ROC curve (AUC) of AE-max, Shell1 E_max, Shell2 E_max, Shell3 E_max and the combination of these 4 parameters in predicting breast cancer was 0.830, 0.906, 0.844, 0.833 and 0.978, respectively. The differences of AE-max, Shell1 E_max, Shell2 Emax and Shell3 E_max among breast masses with different expressions of biological parameters were statistically significant (P < 0.05). The AE-max, Shell1 E_max, Shell2 E_max, and Shell3 E_max of breast masses were all positively associated with the expressions of PR (r =0.612, 0.632, 0.613 and 0.597, all P < 0.05), ER (r = 0.426, 0.463, 0.385 and 0.361, all P < 0.05), HER-2 (r = 0.569, 0.711, 0.603 and 0.587, all P < 0.05) and Ki-67 (r = 0.603, 0.658, 0.553 and 0.611, all P < 0.05). The positive rates of PR, ER, HER-2 and Ki-67 of the malignant breast masses were significantly higher than those of the benign breast masses (P < 0.05), and the presence of lymph node metastasis indicated a higher positive rate of HER-2 (P < 0.05).Conclusions SWE quantitative parameters can effectively differentiate between the benign and malignant breast masses, and are closely related to the biological parameters of breast cancer.