Shear wave elastography (SWE) is useful for the benign / malignant differentiation of solid breast lesions and was included in the 5th edition of the Breast Imaging- Reporting and Data System (BI-RADS). Aim:to investigate the performance of qualitative Shear Wave Elastography (SWE) combined with the conventional US-BI-RADS for detection of malignancy in breast lesions. Methods:This prospective study included 275 female patients with 347 breast lesions. The Conventional US characteristics and SWE colour overlay patterns of each breast lesion were separately recorded and analyzed in accordance with the American College of Radiology (ACR) Ultrasound Lexicon and then classified in accordance with the ACR BI-RADS assessment categories. Results: For differentiation of benign and malignant breast lesions, conventional US-BIRADS had shown sensitivity: 98.08%, specificity: 63.87%, positive predictive value : 68.92%, negative predictive value : 97.60% and accuracy : 79.25%.The statistical indices for the combined analysis of both conventional US-BIRADS and qualitative SWE (colour overlay patterns) for differentiation of benign and malignant breast lesions are: sensitivity: 98.08%, specificity : 81.15%, positive predictive value : 80.95%, negative predictive value : 98.10% and accuracy : 88.76%. Conclusion: Adding qualitative SWE (Colour overlay pattern) to conventional U/S-BIRADS, improves the specificity and overall diagnostic accuracy for detection of malignancy in breast masses.