A wide variety of benign and malignant breast processes may generate hyperintense signal at T2-weighted magnetic resonance imaging (MRI). MRI has been traditionally used in the pre-treatment planning of breast cancer, in assessing treatment response and detecting recurrence. In this comprehensive review, we describe and illustrate the MRI features of a few common and uncommon T2 hyperintense breast lesions, with an emphasis on MRI features that help to characterize lesions based on morphological features, specific appearances on T1-and T2-weighted imaging, and enhancement characteristics on the dynamic post-contrast phase that are either diagnostic or aid in narrowing the differential diagnosis.