The purpose of this study was to retrospectively review sonographic imaging features of estrogen-negative breast cancers and compare tumors with and without human epidermal growth factor type II (HER2) overexpression. Breast sonography findings from a sample of 54 patients with estrogen-negative breast cancer as well as pathological data and HER2 status were reviewed. Sonographic features including size, depth shapes, margin, location, patterns of internal echoes, posterior echoes, orientation, and presence of halo and clinicopathologic data and imaging features were correlated with tumor HER2 status. Based on these 54 patients with estrogen-negative breast cancers, 21 patients were positive for HER2 receptor, and 33 patients were negative for HER2 receptor. Among HER2 positive cancers, irregular shape, microlobulation, indistinct margins, posterior shadowing, a thin halo, heterogeneous internal echoes, and parallel orientation were the most frequent sonographic features. No associations were found between HER-2 status and tumor size, shape, margins, posterior feature, halo, internal echoes, or orientation on sonography