Objective: To discuss the correlation between quantitative shear wave elastography (SWE) and axillary lymph node metastasis and evaluate the ability of shear wave elastography to predict axillary lymph node metastasis. Methods: Data were prospectively analyzed from 370 consecutive patients with invasive breast cancer who had undergone SWE examination and treated by primary surgery. Four elastography images—in each of two orthogonal planes—were taken of each lesion using the Aixplorer ultrasound system (SuperSonic Imagine, Aix en Provence, France). Quantitative measurements were produced and analyzed by Q-box trace. Take the average number of two orthogonal planes as Emean, Emax and standard deviation (SD). Associations between lymph node involvement and mean lesion stiffness, invasive cancer size, tumour location, histologic grade, tumour type, ER expression, PR expression, and HER-2 status were assessed using univariate and multivariate logistic regression. Results: At univariate analysis, invasive cancer size, tumour location, immunohistochemical profile, and stiffness value were significantly associated with nodal involvement. At multivariate analysis, invasive size, tumour location, HER-2, max stiffness and SD maintained independent significance. Nodal involvement rates increased with the Emax, Emean and SD. Conclusion: Stiffness at SWE is an independent predictor of lymph node metastasis and thus can confer prognostic information additional to that provided by preoperative tumour and lymph node assessment and staging.