At present, breast cancer has become the most common female malignancy badly threatening health around the world, which suggests that early diagnosis and treatment are crucial. As a new ultrasound technique, ultrasonic elastography (UE) has developed rapidly and been applied widely. UE provides more significant information about tissue elasticity characteristics on the basis of B-mode ultrasound, and elasticity imagings show stiffness distribution of tissues directly. At the same time, tissue elasticity characteristics are closely associated with pathological component. Therefore, UE provides an important basis for clinical differential diagnosis of breast lesions. This paper reviews pathologic basis and application progress of UE in differential diagnosis of benign and malignant breast lesions.